t1000 user’s manual - user equip: new & used test equipment manual.pdf · would the test set...

Istrumentazioni Sistemi Automatici S.r.l.

VIA BERGAMO 41 - 21020 TAINO (VA) - ITALY OFFICES TEL. +39.0331.956081 - FAX +39.0331.957091 LAB: TEL. +39.0331.956483 - E-MAIL [email protected] WEB www.isatest.com

DATE: 02/02/2006 DOC.MIE10093 REV. 7

T1000 USER’S MANUAL

DOC. MIE10093 Rev. 7 of 138

REVISIONS SUMMARY VISA N PAGE DATE 1 All 26/09/2002 Preliminary issue Lodi.

2 All 20/3/03 Issued Lodi

3 All 20/09/2003 Final revision Lodi

4 99-101 11/11/03 Added the paragraph related to DC voltage supply

Lodi

5 69-76 13/1/2005 Added the paragraph related to differential relay testing

Lodi

6 17; 95 10/9/2005 Added the vector group test for PT transformers. Modified paragraph 2.14

Lodi

7 128, 129 02/02/2006 Added the range change values Lodi


SHORT FOREWORD ....................................................................................................................................................... 6

SAFETY AT WORK........................................................................................................................................................... 7

INTRODUCTION............................................................................................................................................................. 8

1 APPLICATION EXAMPLES .................................................................................................................................... 10 1.1 OVERCURRENT RELAY TESTING ............................................................................................................................... 10

1.1.1. Introduction................................................................................................................................................... 10 1.1.2. Connection to current outputs ...................................................................................................................... 11 1.1.3. I> Threshold and drop-off ............................................................................................................................. 12 1.1.4. I>> Threshold and drop-off........................................................................................................................... 13 1.1.5. Trip and drop-off timing ................................................................................................................................ 13

1.2 OVER AND UNDER VOLTAGE..................................................................................................................................... 14 1.2.1. Introduction................................................................................................................................................... 14 1.2.2. Connection to voltage output ......................................................................................................................... 14 1.2.3. V> Threshold and drop-off ............................................................................................................................ 15 1.2.4. V< Threshold and drop-off ............................................................................................................................ 16 1.2.5. Trip and drop-off timing ................................................................................................................................ 16 1.2.6. Hint: how to test a three-phase voltage relay ................................................................................................ 16 1.2.7. Hint: vector group test for a PT transformer ................................................................................................ 17

1.3 DC VOLTAGE RELAY TESTING .................................................................................................................................. 19 1.3.1. Introduction.................................................................................................................................................... 19 1.3.2. Connection to voltage output ......................................................................................................................... 19 1.3.3. V< Threshold and drop-off ............................................................................................................................ 20 1.3.4. Trip and drop-off timing ................................................................................................................................ 21

1.4 REVERSE POWER RELAY TESTING............................................................................................................................. 22 1.4.1. Introduction.................................................................................................................................................... 22 1.4.2. Connection of the relay................................................................................................................................. 23 1.4.3. P% Threshold and drop-off ........................................................................................................................... 25 1.4.4. Threshold and drop-off of other points ......................................................................................................... 25 1.4.5. Trip and drop-off timing ................................................................................................................................ 25

1.5 DIRECTIONAL RELAY TESTING.................................................................................................................................. 27 1.5.1 Introduction..................................................................................................................................................... 27 1.5.2. Connection of the relay................................................................................................................................. 28 1.5.3. MTA and angle sector.................................................................................................................................... 30 1.5.4. V-I curve test .................................................................................................................................................. 30 1.5.5. Trip and drop-off timing ................................................................................................................................ 31

1.6 OVER AND UNDER FREQUENCY RELAY TESTING....................................................................................................... 32 1.6.1. Introduction................................................................................................................................................... 32 1.6.2. Connection to voltage output ......................................................................................................................... 32 1.6.3. F> Threshold and drop-off ............................................................................................................................ 34 1.6.4. F< Threshold and drop-off ............................................................................................................................ 34 1.6.5. F>> Threshold and drop-off.......................................................................................................................... 34 1.6.6. F<< Threshold and drop-off.......................................................................................................................... 35 1.6.7. Trip and drop-off timing ................................................................................................................................ 35

1.7 FREQUENCY RATE OF CHANGE RELAY TESTING ........................................................................................................ 36 1.7.1. Introduction................................................................................................................................................... 36 1.7.2. Connection to voltage output ......................................................................................................................... 37 1.7.3. MXROC Threshold ........................................................................................................................................ 38 1.7.4. F>> Threshold and drop-off.......................................................................................................................... 38 1.7.5. T2 trip and drop-off timing............................................................................................................................ 38 1.7.6. F> threshold ................................................................................................................................................... 38

1.8 SYNCHRONIZING RELAY TESTING ............................................................................................................................. 40 1.8.1 Introduction..................................................................................................................................................... 40 1.8.2. Connection to voltage outputs ....................................................................................................................... 40 1.8.3. Voltage threshold and drop-off...................................................................................................................... 42 1.8.4. Angle threshold .............................................................................................................................................. 42


1.8.5. Frequency threshold ...................................................................................................................................... 43 1.9 TIMER TEST.............................................................................................................................................................. 45 1.10 LOSS OF FIELD RELAY TESTING............................................................................................................................... 46 1.11 AUTOMATIC RECLOSER TESTING ............................................................................................................................ 50

1.11.1 Introduction................................................................................................................................................... 50 1.11.2 Connection to the relay and recloser ............................................................................................................ 51 1.11.3 Recloser test programming ........................................................................................................................... 52

1.12 DISTANCE RELAY TESTING ..................................................................................................................................... 53 1.12.1 Introduction................................................................................................................................................... 53 1.12.2 Definition of terms ........................................................................................................................................ 54 1.12.3. Relay connection .......................................................................................................................................... 55 1.12.4 Test conduction ............................................................................................................................................. 57 1.12.5 Single phase fault.......................................................................................................................................... 58 1.12.6 Phase to phase fault ...................................................................................................................................... 60 1.12.7 Three phase fault .......................................................................................................................................... 63

1.13 TEST OF CONVERTERS............................................................................................................................................ 66 1.14 TEST OF ENERGY METERS ...................................................................................................................................... 68 1.15 TRANSFORMER DIFFERENTIAL RELAY TESTING WITH D/1000............................................................................. 70

1.15.1 Introduction.............................................................................................................................................. 70 1.15.2 The transformer ............................................................................................................................................ 70 1.15.3 The Restraint and the Differential current .................................................................................................. 71 1.15.4 Connection to the relay ............................................................................................................................ 72 1.15.5 Characteristic curve test........................................................................................................................... 74 1.15.6 Displaying the characteristic with X-Pro 1000........................................................................................ 75 1.15.7 Connections for different transformer connections................................................................................ 77 1.15.8 Second harmonic restraint test ................................................................................................................ 78

2 USER’S GUIDE ........................................................................................................................................................... 79 2.1 HAZARDOUS SITUATIONS ......................................................................................................................................... 79 2.2 CONNECTION TO THE RELAY AND POWER-ON........................................................................................................... 79 2.3 TEST CONTROL......................................................................................................................................................... 80 2.4 CURRENT GENERATION ............................................................................................................................................ 83 2.5 AC VOLTAGE GENERATION FROM MAIN OUTPUT ...................................................................................................... 84 2.6 DC VOLTAGE GENERATION FROM MAIN OUTPUT ...................................................................................................... 85 2.7 AC VOLTAGE GENERATION FROM THE AUXILIARY OUTPUT ...................................................................................... 85 2.8 DC VOLTAGE GENERATION FROM THE AUXILIARY OUTPUT ...................................................................................... 87 2.9 AUXILIARY CONTACT............................................................................................................................................... 88 2.10 THE TIMER ............................................................................................................................................................. 88 2.11 FINDING RELAY THRESHOLDS................................................................................................................................. 89

2.11.1. Introduction................................................................................................................................................. 89 211.2. First threshold trip and drop-off................................................................................................................... 90 2.11.3. Second threshold trip and drop-off ............................................................................................................. 91

2.12 FINDING RELAY TIMINGS ........................................................................................................................................ 91 2.13 BASIC TEST PRINCIPLES .......................................................................................................................................... 93

2.13.1. Introduction.................................................................................................................................................. 93 2.13.2. Parameter vs. time characteristic ................................................................................................................ 93 2.13.3. Parameter vs. parameter characteristic....................................................................................................... 94

2.14 USE OF THE TEST SET AS A MULTIMETER ................................................................................................................ 96 3 TEST SET AND POP-UP MENU .............................................................................................................................. 98

3.1 THE FRONT PANEL.................................................................................................................................................... 98 3.2 DISPLAY AND CONTROL LIGHTS.............................................................................................................................. 100 3.3 THE POP-UP MENU.................................................................................................................................................. 101

4 THE HELL, IT DOESN’T WORK .......................................................................................................................... 108 4.1 INTRODUCTION ...................................................................................................................................................... 108 4.2 ERROR MESSAGES .................................................................................................................................................. 109 4.3 TROUBLE SHOOTING .............................................................................................................................................. 110 4.4 PHYSICAL DESCRIPTION ......................................................................................................................................... 111

4.4.1 Protection fuses ............................................................................................................................................. 113


4.4.2 Auxiliary supplies.......................................................................................................................................... 113 4.4.3 No power at power-on ................................................................................................................................... 115

4.5 AUXILIARY DC VOLTAGE FAULT ................................................................................................................. 115 4.6 NO OUTPUT FROM THE MAIN CURRENT AND VOLTAGE ........................................................................................... 116 4.7 DOES NOT MEASURE THE MAIN CURRENT .............................................................................................................. 116 4.8 THE DISPLAY BACKLIGHT DOES NOT TURN ON........................................................................................................ 117 4.9 THE AC VOLTAGE MEASUREMENT IS NOT STABLE ................................................................................................. 118 4.10 THE TRIP INPUT IS NOT DETECTED OR TIMING ERROR ........................................................................................... 118 4.11 PROBLEMS DURING UPGRADE .............................................................................................................................. 118 4.12 THE ENCODER IS BROKEN .................................................................................................................................... 119 4.13 THE FAULT CANNOT BE FIXED .............................................................................................................................. 119 4.14 CALIBRATION....................................................................................................................................................... 121

4.14.1 Introduction................................................................................................................................................ 121 4.14.2 Calibration procedure ................................................................................................................................ 121 4.14.3 T/1000 output calibration .......................................................................................................................... 122 4.14.4 T/1000 external measurements calibration............................................................................................... 124

5 CHARACTERISTICS............................................................................................................................................. 125 5.1 MAIN AC CURRENT ............................................................................................................................................... 125 5.2 MAIN AC VOLTAGE................................................................................................................................................ 126 5.3 MAIN DC VOLTAGE................................................................................................................................................ 126 5.4 AUXILIARY AC VOLTAGE ...................................................................................................................................... 126 5.5 AUXILIARY DC VOLTAGE ...................................................................................................................................... 126 5.6 TIMER ................................................................................................................................................................... 126 5.7 AUXILIARY CONTACT............................................................................................................................................. 127 5.8 OUTPUTS MEASUREMENT...................................................................................................................................... 127

5.8.1 Current and voltage ...................................................................................................................................... 127 5.8.2 Other measurements ..................................................................................................................................... 128

5.9 EXTERNAL INPUTS MEASUREMENT ....................................................................................................................... 128 5.9.1 Current measurement ................................................................................................................................... 128 5.9.2 Voltage measurement.................................................................................................................................... 128 5.9.3 Other measurements ..................................................................................................................................... 130

5.10 PROTECTIONS....................................................................................................................................................... 130 APPENDIX 1 SPARE PARTS LIST........................................................................................................................... 132

APPENDIX 2 OVERCURRENT RELAYS................................................................................................................ 133


SHORT FOREWORD Dear T/1000 user, I often wondered why the user’s manual is not very much used, even if it includes valuable information. As I am also a user of such manuals, the answer I have given myself is that valuable information are concealed somewhere in the thick thing, and I do not have time to waste to find it. So, either the manual is actually of help, or I ignore it. This is why I decided to arrange this manual in the way exactly opposite to the standard: the introduction is at last page; applications examples are on the top of the manual. The basic idea is that you may read once the device description, while you need application examples more than once; so, why shouldn’t I to put mostly used pages first? The only exception to this organization is next page: it reminds to be cautious when using these test sets. We are on the field since more than 50 years, and no injury has ever been reported; yet, your kids want you back home after work. Have a good work with T/1000! Primo Lodi Q&A Manager


SAFETY AT WORK The Product hereafter described is manufactured and tested according to the specifications, and when used for normal applications and within the normal electrical and mechanical limits will not cause hazard to health and safety, provided that the standard engineering rules are observed and that it is used by trained personnel only. The operating manual is published by the Seller to be used together with the system hereafter described. The Seller reserves the right to modify the manual without warning, for any reason I.S.A. This includes also but not only, the adoption of more advanced technological solutions and modified manufacturing procedures. The Seller declines any difficulties arising from difficulties due to unknown technical difficulties. The seller declines also any responsibility in case of modification of the instrument or of any intervention not authorized by the Seller in writing. The Product is specified and has been tested to operate according to EN 61010-1, with the following operating conditions: . Pollution degree 2: normally, non conductive pollution occurs; . Measurement category 2, for measurement inputs. Would the test set be used beyond these limits, the safety of the test set could be impaired. Mains supply characteristics are: . Voltage: 230 AC, 50-60 Hz, or 115 VAC, 50-60 Hz; . Power consumption: 1 kW maximum. The Product generates voltages and currents that may be lethal to the unadvertised user. Besides, in order to avoid any danger in case of fault inside the Product, the device under test should have the following characteristics: . Connection cables must use safety banana sockets; . Connection sockets must be not accessible; . Input circuits must have an isolation degree at least equal to the one of the product. DO NOT OPERATE THE PRODUCT IF NOT CONNECTED TO GROUND: BECAUSE OF FILTER CAPACITORS, THE CASE WOULD GROW TO A VOLTAGE EQUAL TO THE HALF OF THE SUPPLY, I.E. 110 V (or 55 V). BESIDES, IN THIS SITUATION THERE IS NO FILTERING AGAINST COMMON-MODE NOISE COMING FROM THE MAINS: THIS CAN CAUSE SUDDEN FAULTS. THIS TYPE OF FAULTS IS NOT COVERED BY THE WARRANTY. The connection to ground is provided through the mains supply cable; however, for added safety, the Product should be connected to ground using the dedicated socket. IF THE GROUND IS NOT AVAILABLE AT THE MAINS SUPPLY, CONNECT THE TEST SET TO GROUND USING THE DEDICATED SOCKET. In case of doubt, please contact your Seller. The Seller, and Manufacturer, declines any and all responsibility due to improper usage, or any usage outside the specified limits.


INTRODUCTION The single phase relay test set mod. T/1000 is suited for the testing and adjustments of the following types of relays; the table lists also the paragraph that explains the test procedure. Type of relay IEEE code PARAGRAPH - Distance* 21 1.12 - Synchronizing 25 1.8 - Over/under-voltage 27 - 59 1.2 - Power, varmetric or wattmetric 32 - 92 1.4 - Under current 37 1.1 - Loss of field 40 1.10 - Reverse phase current 46 1.4 - Instantaneous overcurrent 50 1.1 - Ground fault 50N 1.1 - Timed overcurrent 51 1.1 - Power factor 55 1.4 - Directional overcurrent 67 1.5 - Directional ground fault 67N 1.5 - Automatic reclose 79 1.11 - DC voltage 80 1.3 - Frequency 81 1.6 - Frequency rate of change 81 1.7 - Motor protection 86 1.1 - Differential ** 87 1.1 - Directional voltage 91 1.5 - Tripping relay 94 1.9 - Voltage regulation 1.2 - Thermal 1.1 - Timers 1.9 * For distance relays three T/1000 are necessary. ** Differential starter circuit In addition to the above, T/1000 can test: . Converters: V; I; f °; p.f.; W; VAr; f., both 0 to 5 and 4 to 20 mA. . Energy meters, single phase or three phase. The instrument contains three separate generators: . Main generator, which generates either AC current, AC voltage; DC voltage; . Auxiliary a.c voltage generator, that generates an independent, phase shifting a.c voltage; . Auxiliary DC voltage generator, that generates the DC voltage that feeds the relay under test. All outputs are adjustable and metered at the meantime on the large, graphic LCD display. With the multi-purpose knob and the LCD display it is possible to enter the MENU mode that allows setting many functions, which make T/1000 a very powerful testing device, with manual and semi-automatic testing capabilities, and with the possibility to transfer test results to a PC via the RS232 interface. These results can be recorded, displayed and analyzed by the powerful TDMS software,


which operates with all WINDOWS versions, and allows creating a data base of all tests in the plant. The basic T/1000 function is to generate current and voltages and to stop generation as the relay trips. Test results are kept in memory, and can be transferred to a PC at a later time, along with settings. The ease of operation has been the first goal of T/1000: this is why the LCD is graphic, and so large. With it, the dialogue in MENU mode is made easy. Besides, all T/1000 outputs are continuously measured, and output values are displayed, with no extra effort to the operator. Also the show waveform feature can be of help: any doubt about strange measurements, distortion and so on can be solved. This is also why we have added the reduced power feature. Modern relays have a very low burden. As current output is a low impedance voltage generator, adjusting low currents and/or current on low burdens is quite difficult because one has to operate at the very beginning of the adjustment knob. In this situation it is possible to connect resistors in series; however, one must be careful not to exceed the maximum current rating, and the wiring is more complicated. The solution to this problem is just to reduce the available power: this is easily performed via the multi-function knob. With less power, the maximum voltage is reduced by a factor of 4.4; the adjustment span on the knob is increased accordingly. Additional features are: . Two meters, current and voltage, with independent inputs, allow measuring T/1000 outputs or any other source; . An auxiliary contact, that follows START and STOP inputs, allows simulating the circuit breaker; . A set of resistors allows easing output adjustment. The instrument is housed in a transportable aluminum box, that is provided with removable cover and handles for ease of transportation. NOTE: WINDOWS is a trademark of MICROSOFT inc.


1 APPLICATION EXAMPLES In this paragraph, and the following ones, we describe how to operate to test the relay. The description of why we operate this way and of which are test set features are given in the following chapters. So, read the following chapters the first time you use T/1000, and then, once learned about it, apply what you learned as follows. The following examples include all information related to the test. As a consequence, there is repetition passing from one test to the next; however, we preferred to arrange the manual so that it was not necessary to read other paragraphs than the relevant one. The only general comment is that as the relay trips the following data are always saved: . Main current, or main AC voltage, or main DC voltage, according to the selection performed with the push-button (57); . Auxiliary AC voltage; . Auxiliary DC voltage; . Timing. If other measurements are selected by the menu, they will also be saved along with these data. As a consequence, there will be test results that can be not relevant for the test: for instance, Vaux when the relay is an overcurrent one.

1.1 OVERCURRENT RELAY TESTING

1.1.1. Introduction There are many families of time-dependent overcurrent relays. Appendix 1 gives information about how to design the nominal curve, staring from the setting parameters. For the test of undercurrent relays, the following notes are to be used the other way round: the drop-off test becomes the threshold test; the threshold test becomes the drop-off test. The following is the connection schematic.


1.1.2. Connection to current outputs . Power-on T/1000, acting on switch (2): the internal light turns on. . Set the current adjustment knob (6) completely counter-clockwise. . If you wish to use the DC voltage output to supply the relay under test, use knob (20) to adjust the voltage value, that is displayed on the LCD display (23). Connect the DC supply input of the relay to sockets (63). . Connect the relay to the two main current output sockets (13) that correspond to the current to be generated. For the sake of accuracy and ease of adjustment, select the smallest range greater that the desired current. . Connect the TRIP output to the STOP input. . Select the connection socket measurement pressing the push-button (57): the LED turns on. This enables current output measurement. WARNING: if you do not select the output socket, the test displays false current or voltage values. . Select ON and check if you can easily adjust the desired current, acting on knob (6). If the current is reached with a rotation less than one fifth of the total, this means that the burden is very low. In this instance, reduce the output power with the following menu commands: Test control > Test power > 60 VA > ESC The 60 VA LED turns on. Select ON again, and check that the desired current can be reached with ease of adjustment; if the current is not reached, go back and select 300 VA. . Next steps depend upon the type of relay and upon the type of test you want to perform. The following example applies to an overcurrent relay with a time-dependent curve and one (or more) time-independent threshold. Of this relay we want to find and save trip and drop-off thresholds, and also the time-dependent curve.


. Set the save function, as follows. Test control > Save > Confirm at trip > ESC . Set the timer with the following selections: Timer start/stop > START > INT (RET)

STOP > EXT > Clean (Voltage) (RET) Edge ESC

NOTE: stop clean or voltage according to the relay trip contact connections.

1.1.3. I> Threshold and drop-off The first session is finding threshold I>. Select ON; slowly increase the current. As the relay trips, pressing the multi-function knob tripping values can be saved. The TRIP LED (43) turns on for 5 seconds; during 5 seconds, parameters at trip are displayed; then, the standard measurement is restored. Confirm save results pressing the multi-function knob, and proceed. NOTE: stored value is the current as the relay trips. This corresponds to the relay threshold only if the current did not change very much while the relay timing elapsed, so current should be increased quite slowly. A more accurate threshold measurement can be found if the starter contact is available. If threshold measurement was not good because you were moving too fast, do not confirm test results and repeat the test. Next, we find the drop-off threshold for I>. From the trip current above, slowly decrease the current; as the relay resets, save test result. NOTE: stored value is the current as the relay resets; as reset timing is usually very short, current does not change very much at drop-off, and the measurement is accurate.

I (I/IN)

t

I> I>>

t>>

(t>) tmax


1.1.4. I>> Threshold and drop-off The second session is finding threshold I>>. The problem is that the test result criterion is no more to find the limit between no trip and trip; it is instead to find the limit between two different timings: what we have shown as t>, for currents less than I>>, and t>> for currents more than I>>. There are many ways to perform the test; we suggest taking advantage of the Timed generation option, as follows. Set the “Don’t save” function, as follows. Test control > Save > Don’t save > ESC Start from a current more than I>; select ON+TIME, and check for time response. Increase the test current, repeat the test until the relay trips with a delay t>>. Reduce the current, and take note of the timing t>. Compute tmax as 80% of t>. Set the Save function, and Timed test, as follows. Test control > Fault injection > Timed > tmax (RET)

Save > Confirm at trip > ESC Select ON; increase the current starting from a value less than I>>. If the relay trips within tmax, pressing the multi-function knob tripping values can be saved; if not, the test goes OFF with no message. In this instance, select ON again until you find the trip. Confirm save results pressing the multi-function knob, and proceed. NOTE: stored value is the current as the relay trips. This corresponds to the relay threshold only if the current did not change very much while the relay timing elapsed; however, for this threshold the timing is short, so the measurement is accurate. Next, we find the drop-off threshold for I>>. From the trip current above, slowly decrease the current; as the relay resets, pressing the multi-function knob tripping values can be saved.

1.1.5. Trip and drop-off timing Now we can measure trip timings, following the I-t curve with as many points as desired. First thing, restore the Maintained fault injection, as follows Test control > Fault injection > Maintained (RET) Then select the NO or NC level for the relay trip contact: Timer start/stop > STOP > EXT > Clean (Voltage) > NO (NC) ESC Now, press ON and pre-adjust the first test current: as the relay trips, don’t save test result; go OFF. Select ON+TIME: as the relay trips, test goes OFF; pressing the multi-function knob tripping values can be saved. The TRIP LED (43) turns on and parameters at trip are displayed until ON or ON+TIME are selected. Confirm save results pressing the multi-function knob, and proceed with other test currents, until all points to be tested are measured. Now we can measure the drop-off timing. First thing, select the NC or NO level for the relay reset contact: Timer start/stop > STOP > EXT > Clean (Voltage) > NC (NO) ESC Now, press ON and pre-adjust the current. Select OFF+TIME: as the relay resets, pressing the multi-function knob drop-off values can be saved. Confirm save results pressing the multi-function knob, and proceed.


1.2 OVER AND UNDER VOLTAGE

1.2.1. Introduction Voltage relays often have an overvoltage and an undervoltage threshold: for this reason, in the following we use the auxiliary voltage generator, that allows setting the pre-fault and the fault voltage independently of each other. For overvoltage relays it is also possible to use the main output. The following is the connection schematic.

1.2.2. Connection to voltage output . Power-on T/1000, acting on switch (2): the internal light turns on. . If you wish to use the DC voltage output to supply the relay under test, use knob (20) to adjust the voltage value, that is displayed on the LCD display (23). Connect the DC supply input of the relay to sockets (63). . If you use the auxiliary AC voltage, as suggested, first select the auxiliary voltage range, then select the pre-fault + fault mode as follows. AUX VAC/VDC > Aux VAC control > Range (RET)

Mode > Pre-fault+fault > Pre-fault amplitude > (Value) ESC The range should be the closest one to the high threshold to be generated. The pre-fault amplitude is adjusted by the multi-function knob and display; the value is computed from the nominal relay (phase – to – phase) voltage VN: V pre-fault = VN/1.73 Standard values are: 57.8 V for VN = 100 V; 63.5 V for VN = 110 V.


After this adjustment the pre-fault voltage is generated prior to all tests. Select ON: as the test is started, the voltage goes to the fault value, that is adjusted by the knob (20). Pre-adjust the fault value at the same value as the pre-fault. . Connect the TRIP output to the STOP input. . Next steps depend upon the type of relay and upon the type of test you want to perform. The following example applies to an overvoltage and undervoltage relay with one (or more) time-independent threshold. Of this relay we want to find and save trip and drop-off thresholds. . Set the “Automatic save at trip” function, as follows. Test control > Save > Confirm at trip > ESC . Set the timer with the following selections: Timer start/stop > START > INT (RET)



1.2.3. V> Threshold and drop-off The first session is finding threshold V>. Select ON; slowly increase the auxiliary AC voltage. As the relay trips, confirm save results pressing the multi-function knob, and proceed. NOTE: stored value is the voltage as relay trips. This corresponds to the relay threshold only if the current did not change very much while the relay timing elapsed; however, trip timing is usually short, so current does not change very much at release, and the measurement is accurate. If threshold measurement was not good because you were moving too fast, do not confirm test results and repeat the test. Next, we find the drop-off threshold for V>. From the voltage above, slowly decrease the voltage; as the relay resets, pressing the multi-function knob tripping values can be saved. The TRIP LED

V (V/VN)

t

V< V>

t>

VN


(43) turns on for 5 seconds; during 5 seconds, parameters at reset are displayed; then, the standard measurement is restored. NOTE: stored value is the voltage as the relay resets. This corresponds to the relay drop-off only if the current did not change very much while the relay timing elapsed; however, reset timing is usually very short, so current does not change very much at release, and the measurement is accurate.

1.2.4. V< Threshold and drop-off The second session is finding threshold V<. Select ON; slowly decrease the auxiliary AC voltage. As the relay trips, confirm save results pressing the multi-function knob, and proceed. Next, we find the drop-off threshold for V<. From the voltage above, slowly increase the voltage; as the relay resets, confirm save results pressing the multi-function knob, and proceed.

1.2.5. Trip and drop-off timing Now we can measure trip timings, following the V-t curve with as many points as desired. Press ON and pre-adjust the first test voltage (either more than V> or less than V<): as the relay trips, don’t save test result; go OFF. Select ON+TIME: as the relay trips, test goes OFF; pressing the multi-function knob tripping values can be saved. The TRIP LED (43) turns on and parameters at trip are displayed until ON or ON+TIME are selected. Confirm save results pressing the multi-function knob, and proceed with other test voltage, until all points to be tested are measured. Now we can measure the drop-off timing. First thing, select the NO (or NC) level for the relay reset contact: Timer start/stop > STOP > EXT > Clean (Voltage) > NC (NO) ESC Now, press ON and pre-adjust the voltage at a value where the relay trips. Select OFF+TIME: as the relay resets, pressing the multi-function knob drop-off values can be saved. Confirm save results pressing the multi-function knob, and proceed.

1.2.6. Hint: how to test a three-phase voltage relay If you have a three phase voltage relay to test, how can you do it given the fact that T/1000 only has two voltage generators? The problem can be easily solved using the two available voltages with a phase shift of 60°, and connecting them as phase to phase voltages rather than phase voltages. The drawing gives the idea.

V MAIN

V AUX

VN


The two voltages shold have the same amplitude, equal to the phase to phase voltage: the connections is shown here below.

With this connection, the VN socket of the relay is not connected: the VN point will be created by the relay input transformers.

1.2.7. Hint: vector group test for a PT transformer There's an easy way to check the power transformer vector group. Please make reference to the following wiring diagram.


• Connect V main to the transformer HV side phase 1 and 2 (positive and negative).

• Connect V aux to the transformer HV side phase 2 and 3 (positive and negative).

• Adjust the same voltage value on both generators.

• Adjust 240° for Vaux with respect to the mains.

• Connect the measuring input Ext V (the 600 V or the 10 V input, as a function of the transformer ratio) to LV side terminals 1 and 2.

• Select the measurement of the ExtV - Vmain phase angle.

This way, we are generating a three phase voltage on HV side, all voltages with 120° phase shift. But, since phase angle of V12is 0°, the phase shift measured on ExtV per respect to Vmain, divided by 30, gives you the transformer group. Suppose you measure 150°, the transformer group would be 150/30=5.


1.3 DC VOLTAGE RELAY TESTING

1.3.1. Introduction DC voltage relays usually have an undervoltage threshold only. We perform the test using the main DC voltage output, because the auxiliary DC voltage is continuously generated, and cannot be used for trip timing tests. The following is the connection schematic.

1.3.2. Connection to voltage output . Power-on T/1000, acting on switch (2): the internal light turns on. . Set the current adjustment knob (6) completely counter-clockwise. . Connect the relay to the two main DC voltage output sockets (61). . Select the socket measurement pressing the push-button (57): the LED turns on. WARNING: if you do not select the output socket, the test displays false voltage values. . Connect the TRIP output to the STOP input. . The following example applies to an undervoltage relay with one (or more) time-independent threshold. Of this relay we want to find and save trip and drop-off thresholds.


. Set the “Automatic save at trip” function, as follows. Test control > Save > Confirm at trip > ESC . Set the timer with the following selections: Timer start/stop > START > INT (RET)



1.3.3. V< Threshold and drop-off The first session is finding threshold V<. Select ON; increase the DC voltage to VN. The relay will reset; do not confirm the value. Now slowly reduce the voltage; as the relay trips, confirm save results pressing the multi-function knob, and proceed. NOTE: stored value is the voltage as relay trips. This corresponds to the relay threshold only if the current did not change very much while the relay timing elapsed. If threshold measurement was not good because you were moving too fast, do not confirm test results and repeat the test. Next, we find the drop-off threshold for V<. From the voltage above, slowly increase the voltage; as the relay resets, pressing the multi-function knob tripping values can be saved. NOTE: stored value is the voltage as the relay resets. This corresponds to the relay drop-off only if the current did not change very much while the relay timing elapsed; however, reset timing is usually very short, so current does not change very much at release, and the measurement is accurate.

V (V/VN)

t

V<

t<

VN


1.3.4. Trip and drop-off timing Now we can measure trip time: as the DC voltage is removed when we start the test, we have only one value. Press ON and pre-adjust the nominal voltage VN. Select OFF+TIME: as the relay trips, test goes OFF; pressing the multi-function knob tripping values can be saved. The TRIP LED (43) turns on and parameters at trip are displayed until ON or ON+TIME are selected. Confirm save results pressing the multi-function knob, and proceed with other test voltage, until all points to be tested are measured. Now we can measure the drop-off timing. First thing, select the NO (or NC) level for the relay reset contact: Timer start/stop > STOP > EXT > Clean (Voltage) > NC (NO) ESC Now, press ON+TIME: as the relay resets, pressing the multi-function knob drop-off values can be saved. Confirm save results pressing the multi-function knob, and proceed.


1.4 REVERSE POWER RELAY TESTING

1.4.1. Introduction Reverse power relays can be either wattmetric or varmetric. The following note applies to both of them; the only difference is the phase angle between current and voltage. Reverse power relays normally protect generators against reverse power. In fact, when the active power flows from the network to the generator, it means that the generator works as a motor (that’s the reason why, sometimes, these protective relays are called anti-motoring relays). This may cause serious problems because the generator receive power from either turbine and network. Therefore this power will be transformed in:

• Kinetic energy: the generator accelerates; • Thermal energy: the temperature increases.

GENERATORMOTOR

ZS

V

I

E0

Forbiddenzone

I

jXsI

RsI

Eo

δ

ϕV

P

Q

≈ Q

≈ P

In other words, if the flux of power is not promptly interrupted, the life of the generator is seriously in danger. Referring to the above scheme, the voltage V is locked to the network. If the phase angle of the current is higher than ±90°, this means that the active power P is negative (working point in 2nd or 3rd quadrant). The test is performed using the main current generator and the auxiliary voltage generator, at different phase shifts. Parameters involved are three: voltage; current; phase shift; so, in the following, the test is performed at nominal voltage, selecting the phase angle and changing the current to find the threshold at the selected angle. As the setting is in percent of the nominal power, it is possible to use the power measurement, that is available on T/1000.


1.4.2. Connection of the relay The following is the connection schematic.

. Power-on T/1000, acting on switch (2): the internal light turns on. . Set the current adjustment knob (6) completely counter-clockwise. . If you wish to use the DC voltage output to supply the relay under test, use knob (20) to adjust the voltage value, that is displayed on the LCD display (23). Connect the DC supply input of the relay to sockets (63). . First select the auxiliary AC voltage range, as follows. AUX VAC/VDC > Aux VAC control > Range (ESC) The range should be the closest one to the high threshold to be generated. The fault amplitude is adjusted by the multi-function knob and display; the value is computed from the nominal relay (phase – to – phase) voltage VN: V pre-fault = VN/1.73 Standard values are: 57.8 V for VN = 100 V; 63.5 V for VN = 110 V. After this adjustment the fault voltage is generated prior to all tests, and is adjusted by the knob (20). . Connect the relay current input to the two main current output sockets (13) that correspond to the current to be generated. For the sake of accuracy and ease of adjustment, select the smallest range greater that the desired current. NOTE: in case of three phase relay, connect all currents in series. . Select the connection socket measurement pressing the push-button (57): the LED turns on. This enables current output measurement. WARNING: if you do not select the output socket, the test displays false current or voltage values.


. Select ON and check if you can easily adjust the desired current, acting on knob (6). If the current is reached with a rotation less than one fifth of the total, this means that the burden is very low. In this instance, reduce the output power with the following menu commands: Test control > Test power > 60 VA > ESC The 60 VA LED turns on. Select ON again, and check that the desired current can be reached with ease of adjustment; if the current is not reached, go back and select 300 VA. . Connect the relay voltage input to the two auxiliary AC voltage output sockets (62). NOTE: in case of three phase relay, connect all voltages in parallel. . As this is a power relay, it is possible to check directly the P-Q curve, selecting in Other measurements the display of P and Q. This is performed the following way. METERS > OTHER > INTERNAL > P-Q ESC The display shows P and Q along with current, voltage and angle. . The relay has a nominal power PN; the threshold is a percentage of PN, P%. From PN compute the nominal current IN = PN *1.73/ VN. NOTE: in case of three phase relay, IN shall be divided by three. . Connect the TRIP output to the STOP input. . Set the timer with the following selections: Timer start/stop > START > INT (RET)


NOTE: stop clean or voltage according to the relay trip contact connections. . Next step serves to ascertain that the relay is correctly connected; to this purpose we perform two tests in opposite directions. The angle between current and auxiliary voltage is set as follows. AUX VAC/VDC > Aux VAC control > Phase > Reference : Current > (adjust phase) ESC NOTE: the adjustment can be performed only after having adjusted the current output. The two tests are:

• Forward: I = IN; ϕ = 0°. Press ON+TIME: the relay should not trip. • Reverse: I = IN: ϕ = 180°. Press ON+TIME: the relay should trip.

Only if the result of the direction test is correct we can proceed with other tests. . Next steps are the search of the points of the P-Q curve we have selected. The key test is performed at 180°; additional tests are decided by the operator. In general, it is wise to execute at leas two more tests, in order to ascertain that the curve corresponds to the nominal one. In our example we will test at 180° (P%); 120° (P1); 240° (P2).


. Set the “Automatic save at trip” function, as follows. Test control > Save > Confirm at trip > ESC

1.4.3. P% Threshold and drop-off . The first session is finding P%. . Set the current to voltage angle at 180°. . Select ON; slowly increase the current. As the relay trips, pressing the multi-function knob tripping values can be saved. The TRIP LED (43) turns on for 5 seconds; during 5 seconds, parameters at trip are displayed; then, the standard measurement is restored. Confirm save results pressing the multi-function knob, and proceed: the display shows the corresponding single-phase power. NOTE: If the relay is three-phase, power should be multiplied by 3. This can easily be done after transferring test results to X-PRO1000. . Next, we find the drop-off threshold for P%. From the trip current above, slowly decrease the current; as the relay resets, save test result. NOTE: stored value is the current as the relay resets; as reset timing is usually very short, current does not change very much at drop-off, and the measurement is accurate.

1.4.4. Threshold and drop-off of other points . Next sessions serve to find P1, P2 threshold and drop-off. . Set the current to voltage angle at next value. . Select ON; slowly increase the current. As the relay trips, the display shows the corresponding single-phase active and reactive power. If the relay is properly set, the active power should be the same as test before, and should display P%, while the reactive power should be 1.73 * P%. . Next, we find the drop-off threshold. From the trip current above, slowly decrease the current; as the relay resets, save test result.

1.4.5. Trip and drop-off timing Now we can measure trip timing. Press ON and pre-adjust the test current (to more than P%): as the relay trips, don’t save test result; go OFF. Select ON+TIME: as the relay trips, test goes OFF; pressing the multi-function knob tripping values can be saved. The TRIP LED (43) turns on and

P

Q

P%

P2

P1


parameters at trip are displayed until ON or ON+TIME are selected. Confirm save results pressing the multi-function knob. Now we can measure the drop-off timing. First thing, select the NO (or NC) level for the relay reset contact: Timer start/stop > STOP > EXT > Clean (Voltage) > NC (NO) ESC Then, select ON and select OFF+TIME: as the relay resets, pressing the multi-function knob drop-off values can be saved. Confirm save results pressing the multi-function knob, and proceed.


1.5 DIRECTIONAL RELAY TESTING

1.5.1 Introduction These relays are used to protect MV feeders against Earth faults by detecting the residual voltage Vo, the residual current Io and the relative angle. Normally the current is lagging; for neutral isolated lines, ΦIo ≈ -90°; for other earth systems (resistance, Petersen Coil), the phase angle can be less: 40°, 60°. This is also the angle of maximum sensitivity of the relay. Since relay inputs are one current and one voltage, we’ll use I main and V aux to perform the test. The parameters that we will test are:

• The characteristic angle, sometimes called MTA= max torque angle (electromagnetic relays), and the Angle sector, that is half of the operating angle;

• The pick up of Io; • The pick up of Vo.

When testing one parameter we have to set the other two at a value above the pick up. • Test MTA: we keep Vo and Io above the respective pick ups. • Test the Angle sector: we keep Vo and Io above the respective pick ups. • Test the pick up of Io: we keep Vo above the pick up, and the current angle at the measured

Characteristic Angle. • Test the pick up of Vo: we keep Io above the measured pick up, and the current angle at the

measured Characteristic Angle. In this example we’ll suppose we are testing a relay with the characteristic displayed in the graph.

Limits between operating and a non operating zone are at around +115° and +285°. This limits can be found with an angle search, starting from the non operating zone (ΦIR = 180°) towards the operative zone, until the relay trips. Prior to this, we have to make sure that the relay operates.

Operating zone

Non Operating zone

Characteristic Angle MTA


Also, the earth directional relay shouldn’t trip for all values of voltage and current. It is widely accepted that a directional relay characteristic can run inside the dotted line area, as shown in the figure.

0.001 0.01 0.1 1 10

1

10

100 X = CURRENT [ A ] Y = VOLTAGE [ V ]

Phase R Lower Lim it

Characteristic V o - Io at Φ Io = - 90°

• V1=100 V • I1= 5 mA W e want to find this point...

• V1 = 6 V • I1R = 1 A ... and this point !

Non operating zone

O p erating zone

Next tests serve to find some point of the characteristic curve. Note that it is also possible to test the relay with some no-trip test inside the non operating zone, and some trip test in the operating zone.

1.5.2. Connection of the relay The following is the connection schematic.

. Power-on T/1000, acting on switch (2): the internal light turns on. . Set the current adjustment knob (6) completely counter-clockwise.


. If you wish to use the DC voltage output to supply the relay under test, use knob (20) to adjust the voltage value, that is displayed on the LCD display (23). Connect the DC supply input of the relay to sockets (63). . Connect the relay current input to the two main current output sockets (13) that correspond to the current to be generated. For the sake of accuracy and ease of adjustment, select the smallest range greater than the desired current. . Select the connection socket measurement pressing the push-button (57): the LED turns on. This enables current output measurement. WARNING: if you do not select the output socket, the test displays false current or voltage values. . Select ON and check if you can easily adjust the desired current, acting on knob (6). If the current is reached with a rotation less than one fifth of the total, this means that the burden is very low. In this instance, reduce the output power with the following menu commands: Test control > Test power > 60 VA > ESC The 60 VA LED turns on. Select ON again, and check that the desired current can be reached with ease of adjustment; if the current is not reached, go back and select 300 VA. If the adjustment is still difficult, specially in case of low current settings, connect a resistor of the set in series to current output and use the external meter, that has lower measurement ranges. As the no-load voltage output of the 10 A range is 50 V, with 470 Ohm the maximum current is 100 mA; with 1000 Ohm it is 50 mA, and with 2200 Ohm it is 22 mA. . Connect the relay voltage input to the two auxiliary AC voltage output sockets (62). . Select the auxiliary voltage range and the fault mode as follows. AUX VAC/VDC > Aux VAC control > Range (RET)

Mode > Fault > ESC The range should be the closest one to the voltage to be generated. With this selection the auxiliary voltage is continuously generated: we will test the relay modifying the auxiliary voltage and the current according to the point to be tested on the V-I curve. . Set the timer with the following selections: Timer start/stop > START > INT (RET)


NOTE: stop clean or voltage according to the relay trip contact connections. . Next step serves to ascertain that the relay is correctly connected; to this purpose we perform two tests in opposite directions. The angle between current and auxiliary voltage is set as follows. AUX VAC/VDC > Aux VAC control > Phase > Reference : Current > (adjust phase) ESC NOTE: the adjustment can be performed only after having adjusted the current output; if the current is too low, it is possible to adjust the voltage with reference to the mains. The two tests are:

I = IN; V = VN; ϕ = MTA + 180°. Press ON+TIME: the relay should not trip. I = IN; V = VN; ϕ = MTA. Press ON+TIME: the relay should trip.


Only if the result of the direction test is correct we can proceed with other tests.

1.5.3. MTA and angle sector The first tests serve to measure the MTA and angle sector. We will perform a threshold test by moving the test point on a circle in the V-I plane. . Set the “Automatic save at trip” function, as follows. Test control > Save > Confirm at trip > ESC . Select ON. . Set: I = IN; V = VN; ϕ = MTA + 180°: the relay does not trip. . Slowly reduce the phase shift, until the relay trips: ϕ1 trip is found. As the relay trips, pressing the multi-function knob tripping values can be saved. The TRIP LED (43) turns on for 5 seconds; during 5 seconds, parameters at trip are displayed; then, the standard measurement is restored. Confirm save results pressing the multi-function knob, and proceed: the display shows the corresponding single-phase power. . From this phase angle, slowly increase the phase shift, until the relay resets: ϕ1 drop-off is found. As the relay resets, pressing the multi-function knob drop-off values can be saved. . Continue to increase the phase shift, until the relay trips: ϕ2 trip is found. As the relay trips, save the trip values. . From this phase angle, slowly decrease the phase shift, until the relay resets: ϕ2 drop-off is found. As the relay resets, pressing the multi-function knob drop-off values can be saved. From these values, compute: Angle Sector = 0.5 * (360 – (ϕ2 - ϕ1)) MTA = Angle sector - ϕ1

1.5.4. V-I curve test The V-I curve is tested setting the phase shift at MTA, and modifying the current at constant voltage, or the voltage at constant current. In our figure we have two points: P1 = 100 V, 5 mA; P2 = 6 V, 1 A. Test of P1 . Press ON. Set the auxiliary voltage 100 V. . The phase angle is not displayed with very low currents; so, adjust the current angle to 90°, taking the mains as a reference: AUX VAC/VDC > Aux Vac control > Phase > Reference: Current > (90°) ESC

ϕ1

ϕ2

V

I

TRIP AREA

MTA


. Use the 10 A range ; connect the 2200 Ohm resistor in series to Io relay input. For a better reading, connect also in series the 25 mA input of the external measurement, selecting this measurement as follows: METERS > External > 20 mA ESC . Slowly increase the current, until the relay trips: P1 trip is found. As the relay trips, pressing the multi-function knob tripping values can be saved. The TRIP LED (43) turns on for 5 seconds; during 5 seconds, parameters at trip are displayed; then, the standard measurement is restored. Confirm save results pressing the multi-function knob, and proceed: the display shows the corresponding single-phase power. . From this current value, slowly reduce it, until the relay resets: P1 drop-off is found. As the relay resets, pressing the multi-function knob drop-off values can be saved. Test of P2 . Press ON. Set the auxiliary voltage at 0 V. . Use the 10 A range ; there I no problem with phase and current measurements. Adjust the current to 1 A. . Slowly increase the voltage, until the relay trips: P2 trip is found. As the relay trips, pressing the multi-function knob tripping values can be saved. The TRIP LED (43) turns on for 5 seconds; during 5 seconds, parameters at trip are displayed; then, the standard measurement is restored. Confirm save results pressing the multi-function knob, and proceed: the display shows the corresponding single-phase power. . From this voltage value, slowly reduce it, until the relay resets: P2 drop-off is found. As the relay resets, pressing the multi-function knob drop-off values can be saved. Other points can be found the same way. For the sake of accuracy, test at constant voltage down to 8 V, and at constant current from 10 mA up.

1.5.5. Trip and drop-off timing Now we can measure trip timing. . Press ON and pre-adjust I = IN; V = VN; ϕ = MTA: as the relay trips, don’t save test result; go OFF. . Select ON+TIME: as the relay trips, test goes OFF; pressing the multi-function knob tripping values can be saved. The TRIP LED (43) turns on and parameters at trip are displayed until ON or ON+TIME are selected. Confirm save results pressing the multi-function knob. Now we can measure the drop-off timing. . First thing, select the NO (or NC) level for the relay reset contact: Timer start/stop > STOP > EXT > Clean (Voltage) > NC (NO) ESC . Then, select ON and then select OFF+TIME: as the relay resets, pressing the multi-function knob drop-off values can be saved. Confirm save results pressing the multi-function knob, and proceed.


1.6 OVER AND UNDER FREQUENCY RELAY TESTING

1.6.1. Introduction Frequency relay monitor the frequency of generator voltage outputs; if the upper or lower frequency threshold is reached, the relay issues a trip command for the circuit breaker, in order to preserve the generator safety. The test is performed using the auxiliary voltage generator, that allows setting the output frequency. We will take advantage of pre-fault and fault selection, so that: . Pre-fault output is set at nominal voltage and mains frequency; . Fault output has the same amplitude, but frequency is modified according to our test. During the test the relay is powered with nominal voltage amplitude; as the frequency changes, amplitude and phase are not affected . Next steps depend upon the type of relay and upon the type of test you want to perform. The following example applies to a frequency relay with two high and two low thresholds; for both we want to find and save trip and drop-off values.

1.6.2. Connection to voltage output The following is the connection schematic,

F

t

F< F>

T2

FN F<< F>>

T1


. Power-on T/1000, acting on switch (2): the internal light turns on. . If you wish to use the DC voltage output to supply the relay under test, use knob (20) to adjust the voltage value, that is displayed on the LCD display (23). Connect the DC supply input of the relay to sockets (63). . Select the auxiliary voltage range and the pre-fault + fault mode as follows. AUX VAC/VDC > Aux VAC control > Range (RET)

Mode > Pre-fault+fault > Pre-fault amplitude > (Value) ESC The range should be the closest one to the nominal voltage. The pre-fault amplitude is adjusted by the multi-function knob and display; the value is computed from the nominal relay (phase – to – phase) voltage VN: V pre-fault = VN/1.73 Standard values are: 57.8 V for VN = 100 V; 63.5 V for VN = 110 V. After this adjustment the pre-fault voltage is generated prior to all tests, as the unit is OFF. Select ON: as the test is started, the voltage goes to the fault value, that is adjusted by the knob (20). Adjust the fault value at the same value as the pre-fault. . Connect the relay to the auxiliary voltage output sockets (62). . Set the “Automatic save at trip” function, as follows. Test control > Save > Confirm at trip > ESC NOTE: for other selections see the pop-up menu chapter. . Connect the TRIP output to the STOP input. . Set the timer with the following selections: Timer start/stop > START > INT (RET)




1.6.3. F> Threshold and drop-off The first session is finding threshold F>. Select ON, then, modify the output frequency as follows: AUX VAC/VDC > Aux VAC control > Frequency > Adjust Slowly increase the auxiliary AC frequency. As the relay trips, confirm save results pressing the multi-function knob, and proceed. NOTE: stored value is the voltage as relay trips. This corresponds to the relay threshold only if the frequency did not change very much while the relay timing T> elapsed, so, frequency should be changed quite slowly. If threshold measurement was not good because you were moving too fast, do not confirm test results and repeat the test. Next, we find the drop-off threshold for F>. From the frequency above, slowly decrease it; as the relay resets, confirm save results pressing the multi-function knob, and proceed. NOTE: stored value is the frequency as the relay resets. This corresponds to the relay drop-off only if the frequency did not change very much while the relay timing elapsed; however, reset timing is usually very short, so the frequency does not change very much at release, and the measurement is accurate.

1.6.4. F< Threshold and drop-off Now we find the threshold F<. Remaining ON from the above test, slowly decrease the auxiliary AC frequency. As the relay trips, confirm save results pressing the multi-function knob, and proceed. Next, we find the drop-off threshold for F<. From the frequency above, slowly increase it; as the relay resets, confirm save results pressing the multi-function knob, and proceed.

1.6.5. F>> Threshold and drop-off The second session is finding threshold F>>. The problem is that the test result criterion is no more to find the limit between no trip and trip; it is instead to find the limit between two different timings: what we have shown as T1, for frequencies less than F>>, and T2, for frequencies more than F>>. There are many ways to perform the test; we suggest taking advantage of the Timed generation option, as follows. Set the “Don’t save” function, as follows. Test control > Save > Don’t save ESC Start from a frequency more than F>; select ON+TIME, and check for time response. Increase the test current, repeat the test until the relay trips with a delay T2. Reduce the frequency, and take note of the timing T1. Compute tmax as 80% of T1. Set the Save function, and Timed test, as follows. Test control > Fault injection > Timed > tmax (RET)

Save > Confirm at trip > ESC Select ON; increase the frequency starting from a value less than F>>. If the relay trips within tmax, pressing the multi-function knob tripping values can be saved; if not, the test goes OFF with no message. In this instance, select ON again until you find the trip. Confirm save results pressing the multi-function knob, and proceed. NOTE: stored value is the frequency as the relay trips. This corresponds to the relay threshold only if the frequency did not change very much while the relay timing elapsed; however, for this threshold the timing is short, so the measurement is accurate.


Next, we find the drop-off threshold for F>>. From the trip frequency above, slowly decrease the frequency; as the relay resets, pressing the multi-function knob tripping values can be saved.

1.6.6. F<< Threshold and drop-off Now we find the threshold F<<. The procedure is the same as for F>>: measure T1 and T2, then compute tmax = 0.8*T1, and set the timed test to find F<<.

1.6.7. Trip and drop-off timing Now we can measure trip timings, following the F-t curve with as many points as desired. Pre-adjust the first test frequency (either more than F> or less than F<). Select ON+TIME: as the relay trips, test goes OFF; pressing the multi-function knob tripping values can be saved. The TRIP LED (43) turns on and parameters at trip are displayed until ON or ON+TIME are selected. Confirm save results pressing the multi-function knob, and proceed with other test frequencies, until all points to be tested are measured. Now we can measure the drop-off timing. First thing, select the NO (or NC) level for the relay reset contact: Timer start/stop > STOP > EXT > Clean (Voltage) > NC (NO) ESC Now, press ON and pre-adjust the frequency at a value where the relay trips. Select OFF+TIME: as the relay resets, pressing the multi-function knob drop-off values can be saved. Confirm save results pressing the multi-function knob, and proceed.


1.7 FREQUENCY RATE OF CHANGE RELAY TESTING

1.7.1. Introduction This type of relay monitors the line frequency and whenever a quick variation is detected, it operates. Normally it is used to disconnect loads from the line and to preserve the stability of the whole network.

Load 1

Load 2

Load 3

The test is performed using the auxiliary voltage generator, that allows setting the output frequency and the frequency rate of change (ROC). We will use the pre-fault and fault selection, so that: . Pre-fault output is set at nominal voltage and mains frequency; . Fault output has the same amplitude; frequency and ROC are modified according to our test. Next steps depend upon the type of relay and upon the type of test you want to perform. The following example applies to a frequency ROC relay with: . A frequency range, from F< to F>, within which it does not trip; . Absolute min and max frequencies, F<< and F>>, below and above which it trips in time T2; . For frequencies between F< and F<<, or between F> and F>>, it trips with delay T1 if ROC is more than the set threshold MXROC; else, it does not trip. The characteristic curve is the following. In the dashed area the relay trips only if the ROC is higher than the threshold.

F

t

F< F>

T2

FN F<< F>>

T1


1.7.2. Connection to voltage output The following is the connection schematic.


Mode > Pre-fault+fault > Pre-fault amplitude > (Value) ESC The range should be the closest one to the nominal voltage. The pre-fault amplitude is adjusted by the multi-function knob and display; the value is computed from the nominal relay (phase – to – phase) voltage VN: V pre-fault = VN/1.73 Standard values are: 57.8 V for VN = 100 V; 63.5 V for VN = 110 V. After this adjustment the pre-fault voltage is generated prior to all tests, as the unit is OFF. Select ON: as the test is started, the voltage goes to the fault value, that is adjusted by the knob (20). Adjust the fault value at the same value as the pre-fault. . Connect the relay to the auxiliary voltage output sockets (62). . Set the “Automatic save at trip” function, as follows. Test control > Save > Confirm at trip > ESC NOTE: for other selections see the pop-up menu chapter. . Set the timer with the following selections: Timer start/stop > START > INT (RET)

STOP > EXT > Clean (Voltage) (RET)


Edge ESC NOTE: stop clean or voltage according to the relay trip contact connections.

1.7.3. MXROC Threshold The first session is finding the MXROC threshold; we will start testing the positive ROC. The ROC threshold cannot be found as usual, modifying the ROC until the relay trips: as we do, the frequency changes, and the relay would trip because of thresholds F>> or F<<. The following session is therefore a series of trip tests performed at different values of ROC. The threshold is found when we have two values of ROC, ROC(31) and ROC(32), ROC(31) < ROC(32), where: . For ROC(31) the relay does not trip; . For ROC(32) the relay trips; . The difference ROC(32) – ROC(31) is small enough for the desired test accuracy. First of all, set the maximum test time as 1.5 * T1, so that we do not waste time: Test control > Fault injection > Timed > 1.5*T1 (RET)

Save > Confirm at trip > ESC Now, set the starting frequency to F>; then, set the first value for ROC: AUX VAC/VDC > Aux VAC control > Frequency > Adjust F> (RET) Adjust ROC Press ON+TEST, and see if the relay trips. Two possibilities: . Trip: don’t save the result; reduce the ROC and repeat until the relay does not trip. Now increase the ROC again: as the relay trips, save test result. . No trip: increase the ROC and repeat until the relay trips: as it does, save test result. With this test we also measure the timing T1. Repeat now the test, with a starting frequency equal to F<, and with the same value for ROC, but with negative sign.

1.7.4. F>> Threshold and drop-off The test procedure is the same as the one for the frequency relay; tmax must be set to 0.8*T1.

1.7.5. T2 trip and drop-off timing The test procedure is the same as the one for the frequency relay; tmax must be set to 0.8*T1.

1.7.6. F> threshold This threshold cannot be checked directly (unless a starting output is available; in this instance, the test is the same as for the frequency relay). If no starting output is available, proceed as follows. . Program the starting frequency = FNOM, and a ROC greater than MXROC, say ROC(33).


. Press ON+TIME and check for the trip time Tt. This delay is the sum of T1 plus the time it has taken to reach F> (or F< with negative ROC); so: . Compute F> = (Tt – T1)*ROC + FNOM


1.8 SYNCHRONIZING RELAY TESTING

1.8.1 Introduction The purpose is to test the synchronising device that allows a generator to be put in parallel to a live power line. There are three conditions that must be verified: Voltage difference below a certain value; || V1- V2 || < 5 V

Frequency difference below a certain value; || F1 - F2 || < 0.1 Hz

Angle difference below a certain value. || Φ1- Φ2 || < 5°

When these three conditions are reached, the relay will give permission to close the switchgear and connect the generator to the power line. These conditions are detected by measuring and comparing V1 from the generator and V2 from the power line: we simulate this situation on T/1000 connecting an input to the main AC voltage output, and the other one to the auxiliary voltage output. We will take advantage of the fact that the auxiliary voltage output can have a different amplitude, can be phase shifted, and can have a different frequency as compared to the main AC voltage output. Normal synchrocheck relays measure the phase to phase voltage on both sides of the Circuit Breaker. This means that the voltage we need to apply might be 100V, or 110V or 115V, depending on the nominal voltage.

Note that in the following, all tests will start from a non synchronized condition. Consider that prior to test start the main voltage output is OFF; so, threshold tests are performed the following way:

. After pressing ON, values are adjusted first so that the relay does not give permission;

. We make sure that the relay is not tripped looking at light (42); then, we slowly modify the parameter until the relay trips. It may occur that the relay does not trip, even if you have reached the minimum value: this is because you moved too fast. Normally you should reach the limit (VN, or 0°, or 50 Hz) in 20 s or more; so, in this instance, repeat the test more slowly.

1.8.2. Connection to voltage outputs The following is the connection schematic.

G 3 ≈

SYNCHROCHECK RELAY



Mode > Fault > (RET) The range should be the closest one to the nominal voltage. After this adjustment the auxiliary voltage is generated prior to all tests, as the unit is OFF, and during the test; the amplitude is adjusted by the knob (20). . Select the main AC voltage output measurement acting on push-button (57), so that light (53) turns on. . Connect the relay input V1 to the main AC voltage output sockets (60), and the relay input V2 to the auxiliary voltage output sockets (62). . Set the “Confirm at trip” function, as follows. Test control > Save > Confirm at trip > ESC NOTE: for other selections see the pop-up menu chapter. . Connect the TRIP output to the STOP input. . Set the timer with the following selections: Timer start/stop > START > INT (RET)




1.8.3. Voltage threshold and drop-off We start from a situation where:

. Amplitudes are different;

. Phase is 0°;

. Frequency is the same (the mains).

From this, we will modify an amplitude, until the relay trips: this is the voltage threshold. There are two thresholds, above and below VN: the test will be performed first with V2 > V1, and then with V2 < V1.

. Press ON, and adjust V1 to VN.

. Press OFF, and adjust the value of V2 to a value greater than VN, that is outside the permission (for instance, 110 V). . Now, press ON again, check that the relay is not tripped, and slowly reduce the voltage until the relay trips: at this moment, confirm save results pressing the multi-function knob, and proceed: the high voltage threshold V> is found. NOTE: Stored values are the voltages as relay trips. This corresponds to the relay threshold only if the voltage did not change very much while the relay relay timing T1 elapsed; soothe voltage should be changed quite slowly. If threshold measurement was not good because you were moving too fast, do not confirm test results and repeat the test. . Next, we find the drop-off threshold for V>. From the voltage above, slowly increase it; as the relay resets, confirm save results pressing the multi-function knob, and proceed. NOTE: stored values are the voltages as the relay resets. This corresponds to the relay drop-off only if the voltages did not change very much while the relay timing elapsed; however, reset timing is usually very short, so the voltage does not change very much at release, and the measurement is accurate. . Now, repeat the procedure for V<. The starting voltage (pre-fault and fault) will be less than VN (for instance, 90 V); the threshold and drop-off for V< are found.

1.8.4. Angle threshold We start from a situation where:

. Amplitudes are the same, and equal to VN;

. Phase is different: it can be more or less than zero; two angle thresholds, A> and A<, will be found;

. Frequency is the same (the mains).

From this, we will modify the phase angle, until the relay trips: this is the angle threshold. The test will be performed first with A > 0°, and then with A < 0°.

. Press ON, and adjust V1 to VN.

. Press OFF, and adjust V2 to VN.

. Press ON, and adjust the phase angle of V2 with respect to V1 at a value outside the permission (for instance, 45°):


AUX VAC/VDC > Aux VAC control > Phase > Reference : voltage> (Value) (RET) . Now, check that the relay is not tripped, and then slowly reduce the phase angle until the relay trips: at this moment, confirm save results pressing the multi-function knob, and proceed: the high angle threshold A> is found. . Next, we find the drop-off threshold for A>. From the angle above, slowly increase it; as the relay resets, confirm save results pressing the multi-function knob, and proceed. Now, repeat the procedure for A<. The starting angle will be less than 0° (for instance, 315°); the threshold and drop-off for A< are found.

1.8.5. Frequency threshold

The frequency test is much more difficult, because any frequency slip between two voltages, leads to a phase angle shift between them. An example will better explain what happens.

Let’s consider the first voltage V1 at FNOM: it could be represented by a vector turning at 50 (6) rounds per second. Consider now the second voltage V2 at 50.1 Hz: it could be represented by a vector turning at 50.1 rounds per second. This means that V2 turns slightly quicker than V1, so V1 sees V2 turning at a frequency of ∆F = 50.1-50 = 0.1Hz: 1 turn every 10”. This means an angle variation of 360° / 10s = 36°/s.

If we have a relay where:

. Angle sector = ± 5°;

. Operating time: 0.1s,

the maximum frequency differential that allows the relay to trip can be computed as follows.

. Total operating angle sector: 5+5=10°;

. Maximum angle ROC: 10°/0.1s = 100 °/s;

. Maximum frequency differential. Since 360°/s correspond to 1Hz, 100°/s = 100°/360° = 0.278 Hz.

So, these parameters are related to each other.

This discussion leads also to the mode of performing the test:

. The voltages should be shifted by the maximum allowed angle plus something, so that we start from the not synchronized condition (in our instance, - 6° or + 6°);

. Start the test with the programmed frequency differential: negative differential starting from the negative angle limit;

. The frequency limit is found by a series of tests with different frequencies around the specified limit;

. The test will have a maximum time equal to a multiple of the operating time (for instance, 2 times). However, for some relay the enable is given only after a complete tour in the enabled situation; in this instance, test time is computed as follows:

(test time) = 1.1 * 1 /(FNOM – FTEST)

The fact that we have to start the test from the not synchronized condition is critical, because:

. When we are OFF, voltage V1 is not applied;


. If we start the test by applying V1 that has a given phase shift and frequency differential with respect to V2, the relay could behave the wrong way. To avoid this, we take advantage of the pre-fault duration selection, during which V1 and V2 at nominal frequency, but with the programmed phase shift, for time that allows the relay to reset; after this, test starts by changing only the frequency of V2.

This explained, the test procedure is the following.

. Adjust the pre-fault amplitude of V2 to VN: AUX VAC/VDC > Aux VAC control > Range (RET)

Mode > Pre-fault+fault > Pre-fault amplitude > (Value) (RET) Pre-fault duration > (TPF) ESC

. Press ON, and adjust: V1 to VN; the phase angle of V2 with respect to V1 to the first angle (for instance, - 6°); the fault frequency to the first test value: AUX VAC/VDC > Aux VAC control > Phase > Reference : voltage> (Value) (RET) > Frequency > Adjust > (FTEST) ESC . Now, press ON+TIME and check if the relay trips. - The relay trips: increase the frequency (with FTEST > FN) by the desired accuracy, and repeat until the relay does not trip. Program the last frequency when it tripped, start the test and save the test result. - The relay does not trip: decrease the frequency (with FTEST > FN) by the desired accuracy, and repeat until the relay trips: as it does, save the test result. . The test is repeated with FTEST < FNOM. The procedure gives also trip times.

TEST OFF ON + TIME

V1 AMPLITUDE VN

V2 AMPLITUDE VN

V2 FREQUENCY FN FTEST

PRE-FAULT TIMING T PF TIMING MEASUREMENT

ANGLE V1-V2

FN

START ANGLE


1.9 TIMER TEST It is possible to test timers by using the output (67). The test is performed like the time delay test for current relays. The following is the connection schematic.

Connect the start of the timer to the normally open or normally close contact of sockets (67), depending on the type of timer under test. Connect the output of the timer to STOP input sockets (65). Start the test pressing ON+TIME: the timer will measure the time between the closing of the contact and the intervention of the timer.


1.10 LOSS OF FIELD RELAY TESTING The typical connection schematic is the following.

The relay monitors voltage and current outputs of the protected generator, and whenever a fault condition is detected, the relay will cause the switchgear to trip in order to preserve the generator safety. When the generator looses the rotoric magnetic field, the working point moves, in the plan R-X, towards the X-axis.

-10 -8 -6 -4 -2 0 2 4 6 8 10

-20

-16

-12

-8

-4

0

4

Resistance

Reactance

Relay CharacteristicGenerator Working Point

The relay detect the loss of field fault when the working point enters the relay characteristic curve (the circle). The typical parameters for LOF relays are the following.


K1 : circle diameter; expressed in % of ZN; K2: offsert; expressed in % of ZN;

3*INVN

ZN =

The characteristic curve depends upon: voltage; current; phase angle between them. The test of the characteristic curve is therefore performed by a number of threshold tests, where each point is found by setting two parameters as fixed and changing the third one. The selection of which parameter to keep fixed and which one should be changed asks for some more consideration. Let’s start with the test of point A, that means to measure the parameter K2. Finding it means to move from a point having zero impedance and increasing the impedance along the –X axis. As we have to generate voltage and current at a given phase angle, the first step is to convert impedance into these parameters. Steps to be followed are: . Compute the impedance corresponding to K2 and K1. For instance, if we have the following setting:

K2

K1

R

X

A

B

C

R

X

D

C’


- VN = 100 V; - IN = 5 A; - ZN = 11.56 Ohm; - K2 = 0,1; - K1 = 1 Then: ZA = 1.156 Ohm; ZB = (K1+K2)*ZN = 12,72 Ohm. . Choose the parameters corresponding to point A. As Z = V/I, taking V as the reference, on the X axis the I angle is – 90°, or 270° ; on the –X axis it is 90°. Now, as we want to move from the point with 0 impedance down to A, it is apparent that the test is best performed by setting a constant value for the current, say IT, and modifying the voltage. The zero impedance point corresponds to V = 0; the point A corresponds to the voltage VA = ZA * IT. In our instance, if we choose It = 5 A, then VA = 5.78 V. In conclusion, the test of point A is conducted by: - Setting the current at IT = 5 A; - Setting the I angle at 90°; - Increasing the voltage from 0 until the relay trips. Next point to be tested is B: how will we perform the test? As per point A, we can set the starting current at 5 A; but, what about the starting voltage? As you can see in the diagram, you have to start from a voltage VS that must be HIGHER than VS = ZB * IT = 63.6 V, Then DECREASE the voltage rather than increasing it, until the relay trips. In our instance, starting from 80 V and decreasing it would do. Next, we want to test point C: how to do it? One could compute the corresponding angle, and perform the test as per A or B; however, minor errors in the angle would cause big errors; C could also be missed. In this situation, the way is to compute the current and voltage corresponding to ZC, and modify the phase angle between them. In our instance: ZC = ZA + (ZB-ZA)/2 = 6.94 Ohm; IT = 5 A; VC = 34.68 V. The test is performed applying these current and voltage at the angle of 0°, and then increasing the angle until the relay trips. Note that if you use the same current and voltage, start from 180° and decrease the angle, you get the symmetric point C’. Last, what about testing other points, like D? You can either set current and angle and decrease the voltage, or set current and voltage and decrease the angle. The following is the connection schematic.


1.11 AUTOMATIC RECLOSER TESTING

1.11.1 Introduction The purpose is to test the recloser device, that allows to reduce the downtime caused by transient faults. The protection device can be: overcurrent; earth directional, distance. The recloser operation is to issue a close command some time after the trip command. After the first close command, the reclose typically checks if a new open command is issued within a so-called reclaim time. Two possibilities: . No trip command within the reclaim time: the reclose resets its internal logic; any further fault starts a new sequence; . Trip command within the reclaim time: the reclose issues a new close command, possibly after a different delay; the procedure continues until the maximum number of close commands has been reached, after which no further close command is issued. The goal of the test is to measure: . Reclaim time TR; . Reclose timings RX, that may be different during the test; . Pre-set maximum number NC of close commands. The test is performed taking advantage of the features offered by T/1000, which is summarized in the following. FAULT 1 2 TRIP (STOP) 1 2 RECLOSE (START) 1 2 TIME MEASUREMENTS D1 R1 D2 R2 TD When the Reclose test is selected, it is possible to program: . The delay TD between the Reclose command and the next fault; . The number of tests. The test set measures: . All trip delays D1, D2… of the sequence; . All reclose delays R1, R2… of the sequence: they are measured from the trip command falling edge. The reclaim time test cannot be performed directly, unless the recloser has an auxiliary output that trips as it expires (typically, this is not the case). For this reason, the reclaim time is tested with two tests, as follows: . First test: TD is programmed greater than the set reclaim TR, for instance 1.05*TR. The number of tests can be T = NC+1, if the reclose delay does not change after the first on, or 2. After TD the


reclose must always issue the close command; there is no evolution in the time delay. This behavior confirms that faults occur after TR has expired. FAULT 1 2 T TRIP (STOP) 1 2 T RECLOSE (START) 1 2 T TIME MEASUREMENTS D1 R1 D2 R2 TD . Second test: TD is programmed smaller than the set reclaim TR, for instance 0.95*TR. The number of tests is T = NC+1. After TD the reclose will issue the close command only until the programmed number of reclose is reached; after which, no more reclose command is issued; besides, there can be an evolution in the time delay (fast reclose to slow reclose). This behavior confirms that faults occur before TR has expired. The two tests together allow verifying TR with the set accuracy (for instance, 5%). The second test allows also to verify the reclose timings RX and the number of reclose commands, NC. FAULT 1 2 T TRIP (STOP) 1 2 T RECLOSE (START) 1 2 TIME MEASUREMENTS D1 R1 D2 R2 TD NOTE: the last reclose command is missing; the test stops as the programmed maximum time is reached; the last timing is 9999 s (equivalent to no trip).

1.11.2 Connection to the relay and recloser The following is the connection schematic.


The connection is the following. . The test is performed on the pair made of the relay and the recloser. All connections from the relay to the recloser shall be left. . Current and voltage outputs of T/1000 will be connected to the relay, according to the type of relay. The instructions for the connection are given in the paragraph related to the relay. . The relay trip command shall be connected to the STOP input of T/1000. . The recloser’s reclose command shall be connected to the START input of T/1000. . If you wish to use the DC voltage output to supply the relay under test, use knob (20) to adjust the voltage value, that is displayed on the LCD display (23). Connect the DC supply input of the relay and recloser to sockets (63).

1.11.3 Recloser test programming First of all, press ON and pre-set current and voltage values such that the relay trips. Note that after this operation it is necessary to reset the internal memory of the recloser: this is achieved by removing for a short time the auxiliary supply. Next, set the maximum test time TM, which shall be greater than the longest reclose delay. Note that if the reclose delay changes from fast reclose to slow reclose, it is necessary to program a time longer than the slow reclose delay. This makes the test time rather long, as these times can be minutes. TEST CONTROL > Fault injection > Timed (TM) ESC Next, select the Recloser test on the main menu as follows: TEST CONTROL > Test mode > Recloser test (TD ; T) ESC Start the test with ON+TIME. For each fault X, the display shows on one line two test results : the trip delay DX and the reclose delay RX. Test result time are four digits with autoranging, so that the percent accuracy is the same for fast and slow reclose times. It is possible to monitor the test evolution looking at these times and also at the STOP and START lights ; the TRIP light follows the stop. For the first test, all tests will have two meaningful timings ; for the second one, after the last test the START light will not turn on : this confirms that the recloser has expired all the programmed reclose attempts. The last time result will be 9999 s, confirming that there was no trip within the programmed maximum time.


1.12 DISTANCE RELAY TESTING

1.12.1 Introduction The test of distance relays is possible only with three T/1000, taking advantage of the EXTERNAL test start feature. The test of distance relays can be performed the following ways: . With a three phase supply, it is possible to simulate single phase, phase to phase or three phase faults. . With single phase supply, single phase or phase to phase faults can be simulated. There are two difficulties to perform distance relay testing: . It is necessary to compute the fault value; from test result, it is necessary to compute back the corresponding fault impedance. This task is easy with single phase and three phase fault; a bit cumbersome with phase to phase faults. . Currents are in phase with the power supply. This means that it is necessary to choose the proper T/1000 power supply connection as a function of the type of power supply (single phase or three phase), and to compute voltage phase angles accordingly. Last, it is necessary to understand very clearly what we mean when we say “test the setting”. First of all, let us consider a possible characteristic of the distance relay to be tested, that is designed in the R-X plane. There are very many different shapes, but the shape does not affect the testing. The first decision for the operator is to select the angle at which he wants to perform the test. It can be that purpose of the test is to check a limited number of settings; if so, they are typically given at

R

X

Z1

Z2

Z3


the line angle (usually 75° to 85°), and possibly also at 0° and 90°. Please note that this angle is the F (I-V) angle to be used during the test, but WITH NEGATIVE SIGN: the reason is that Z = V / I As the current is at the denominator, the angle sign is changed. Now it must be understood that once the angle is selected, the phase angle line intercepts the characteristic at the setting values; this is represented in the Z-t plane by the following curve. During our tests, we do not modify the test angle and the test current: as a consequence, the fault impedance becomes a function of the test voltage only. Now, the point is that a setting of nominal value Z is verified when we find that: . With a fault at Z-d the relay trips in zone N; . With a fault at Z+d the relay trips in zone N+1. The value d can be made as small as desired; however, ad d is smaller, the step between zones becomes uncertain, and not exactly steep. If the above is verified, then the relay setting is Z. In conclusion, you always need two tests to verify the setting; you cannot compute the values corresponding to Z, start one test and decide if the setting is correct. This makes the testing more difficult, especially with phase to phase faults. As example, Z1 is checked when: . With Z1-d, the relay trips with delay T1; . With Z1+d, the relay trips with delay T2. In a similar way, time limits for Z2 are T2 and T3, and for Z3 are T3 and no trip. As you see, testing distance relays can be difficult; however, it can be very important to be able to do it anyway.

1.12.2 Definition of terms The definition of parameters is the following.

Z Z1 Z2 Z3

t

T1

T2

T3


. VN = Nominal relay phase voltage: it is the nominal voltage V divided by 1.73. For V = 100 V, then VN = 57,8 V; for V = 110 V, VN = 62,5 V.

. IN = nominal relay current; usually, 5 A or 1 A.

. Z = fault impedance, on the secondary side.

. KoL = zero-sequence coefficient; it is a number; usually it ranges between 0.5 and 2.

. If = fault current. The fault current If shall be greater than the zero voltage starting current IV0, and less than IMAX, that is computed as a function of the maximum fault impedance to be simulated ZM, as follows:

Single phase faults: IMAX = VN / (ZM * (1 + KoL)) Phase to phase faults: IMAX = VN / (2 * ZM) Three phase faults: IMAX = VN / ZM

If the test current is greater than IMAX, the last setting cannot be found. Usually its value is chosen between 5 and 10 A (for IN = 5 A), or from 1 to 2 A (for IN = 1 A).

. Vf = fault voltage; it is computed as a function of Z and the other parameters.

. F (I-V) = angle of the fault current with respect to the fault voltage, taken as the reference. Typically, tests are performed with F (I-V) ranging from 0° to 90°.

1.12.3. Relay connection The first thing is to connect the three T/1000 to the relay to be tested. The connection depends upon the type of test: single phase, phase to phase; three phase. The phase angle of voltages will change as a function of the type of test, and also as a function of power supply available: single phase or three phases. The following table summarizes power supply connections. FAULT SUPPLY VS1 VN1 VS2 VN2 VS3 VN3

3 PH V1 VN V2 VN V3 VN SINGLE 1 PH V1 VN V1 VN V1 VN

THREE 3 PH V1 VN V2 VN V3 VN PH 1-2 3 PH V1 VN VN V1 V3 VN PH 2-3 3 PH V1 VN V2 VN VN V2 PH 3-1 3 PH VN V3 V2 VN V3 VN PH 1-2 1 PH V1 VN VN V1 V1 VN PH 2-3 1 PH V1 VN V1 VN VN V1 PH 3-1 1 PH VN V1 V1 VN V1 VN

Note: in phase to phase faults, currents are equal in module and opposite in phase.


CONNECTION OF THREE T/1000 TO THE DISTANCE RELAY


The last problem is that there is no special mark on the power supply cord that tells the phase supply apart from the neutral supply. In order to be sure about power supply connection, it is necessary to meter the phase angle between main voltage outputs, which are in phase with the power supply. The procedure is the following. . Connect the three T/1000 to the mains as per the above schematic. . Connect the main voltage output of T/1000-2 to the external measurement input of T/1000-1. . On T/1000-1 select the external measurement. . On both T/1000, select the main voltage output measurement. . Press ON on both T/1000, and adjust the main voltage output to 100 V. . Check that the displayed angle is the following one; if not, reverse the supply of T/1000-2. . Repeat the sequence with T/1000-3. FAULT SUPPLY T/1000-

2 T/1000-3

3 PH 240° 120° SINGLE 1 PH 0° 0°

THREE 3 PH 240° 120° PH 1-2 3 PH 180° 120° PH 2-3 3 PH 240° 60° PH 3-1 3 PH 60° 180° PH 1-2 1 PH 180° 0° PH 2-3 1 PH 0° 180° PH 3-1 1 PH 180° 180°

1.12.4 Test conduction Of the three T/1000, we will consider the one connected to phase 1 as the “Master”: it drives the test of all T/1000 as follows. The test is performed taking advantage of the External selection on Fault injection: in this mode, fault generation and time measurement are performed only when the START input is sensed. The reason why we define T/1000-1 as the “master” is because it is its auxiliary contact that starts the test of all T/1000, including itself. In conclusion, the test sequence will be the following: . Select the External mode on all T/1000: TEST CONTROL > Fault injection > External ESC . Program the auxiliary contact closure on T/1000-1: TEST CONTROL > Auxiliary contact (delay = 0) ESC . Press ON+TIME on T/1000 no. 2 and 3: no output is generated; timer does not start; . Press ON+TIME on T/1000-1: outputs are generated and timers start on all T/1000. . This sequence is to be followed whenever a fault is generated. The other selection to perform on all T/1000 is the pre-fault range and mode: AUX VAC/VDC > Aux VAC control > Range RET > Mode > Pre-fault + fault > Pre-fault amplitude > Pre-fault phase Set the range at the value closer to VN: usually it is 62.5 V. The pre-fault amplitude value is VN.


For single phase and three phase faults the pre-fault phase is zero; for phase to phase faults see below.

1.12.5 Single phase fault In single phase faults, voltage and current vectors are modified during the test as shown in the following figure.

VR N

VT

VR

VS

−ϕ IR

This instance applies to phase 1 fault: as test starts, the value of V1 goes from VN to Vf; at the meantime, If is applied, at the pre-set phase angle. 1) Fault current The current will be adjusted only on the faulty phase (1, 2 or 3), while the others remain at zero; its value is the one selected by the operator (for instance, 10 A). 2) Healthy voltages phase angles Choose the test angle in the R-X plane. If the distance relay is set on the CT star point towards Busbar, the angle F (I-V) has the same value but negative, otherwise it has the same value. These angles depend upon the test angle and the supply: see the table below. The angle is adjusted prior to actual zone testing, as follows. Start the test; adjust the fault current; adjust the fault voltage at 30 V. Now select the auxiliary Vac phase with respect to the current, as follows: AUX VAC/DC > Aux Vac control > Phase > Reference: current ESC This adjustment will not be modified during tests. SUPPLY FAULT PHASE 1 PHASE 2 PHASE 3 3 PHASE ANY F (I-V) F (I-V) F (I-V)

PHASE 1 F (I-V) F (I-V) + 240° F (I-V) + 120° PHASE 2 F (I-V) + 120° F (I-V) F (I-V) + 240°

1 PHASE

PHASE 3 F (I-V) + 240° F (I-V) + 120° F (I-V) 3) Zone limits test


Given the fault impedances Z1, Z2, Z3, Z4 of the zone limits, compute as follows the corresponding fault voltages V1, V2, V3, V4: Vf = Z*If*(1+KoL) For instance: KoL = 1; If = 10 A Vf = 20 * Z These voltages are the limits between following zones, as follows: VOLTAGE < V1 > V1 < V2 > V2 < V3 > V3 < V4 > V4 TIMING T1 T2 T2 T3 T3 T4 T4 NO TRIP ZONE LIMIT

1 2 3 STARTER

Where: T1, T2, T3, T4 are respectively the time settings for zones 1, 2, 3, 4 (case of three zones plus the starter). Once fault current and pre-fault voltage amplitudes have been adjusted to VN, stop the test and start again. Adjust the fault voltage of the selected phase at a value slightly less than V1, VT11: the trip time should be the one of zone 1. Slightly increase the fault voltage and start again with value VT12: trip time should become T2. The procedure can be repeated at will, until the first zone is checked with the desired accuracy: the result is Z1 = (VT11+VT12)/(2*If*(1+KoL)) Once a limit has been found, repeat the test for other zone limits. During these tests, current and phase are no more modified. Example. Let us assume that the distance relay to be tested has the following settings at line angle (75°). ZONE LIMIT ONE TWO THREE STARTER IMPEDANCE Ohm

0.2 0.4 1 2

TIMING s

0.05 0.3 0.6 1.2

Let us assume: KoL = 1; IV0 = 2.5 A; VN = 57.8 V (100 V). Maximum test current is: IMAX = 57.8/(2*(1+1)) = 14.4 A. We choose If = 8 A; the corresponding zone limit voltages are: V1 = 3.2 V; V2 = 6.4 V; V3 = 16 V; VSTART = 32 V. We adjust the current of I1 to 8 A; the V-I phase angle is -75° (line side) or 105° (Busbar side); V1 fault voltage is 3.2 V; V2 and V3 are 57.8 V.


We start the test at 3 V; if trip time is 0.05 s we slightly increase V1 and start again, until trip time becomes 0.3 s: let us assume that VT11 is 3.5 V and VT12 is 3.6 V. This means that first zone limit is 0.221 Ohm; the error is + 10%. If instead with 3 V the trip time is 0.3 s we reduce V1 and start again, until trip time becomes 0.05 s: let us assume that VT11 is 2.9 V and VT12 is 3 V. This means that first zone limit is 0.185 Ohm; the error is -7.4%. The test continues with the following fault voltages, until all limits are tested. The starter limit is found between 1.2 s trip time and no trip. This limit can also be found starting the test with V1=VN, and then lowering V1 until the relay trips. If the starter is over-current, and it is desired to find threshold settings IVN and IVo, the test is performed as a time independent over-current relay, but test voltage will be 0 V for the test of IVo, and VN for the test of IVN. The test can continue as follows: . Test the same settings, with faults on phases 2 and 3; . Test other types of fault.

1.12.6 Phase to phase fault In phase to phase faults, voltage and current vectors are modified during the test as shown in the following figure, which refers to the fault of phases 2 and 3. Note that in this type of fault the fault voltage is the phase to phase voltage; fault currents are identical in module and opposite in phase; the fault current angle is metered with respect to the phase to phase voltage. This situation makes the test of phase to phase faults quite cumbersome. For each test, it should be necessary to modify the fault voltage amplitude and phase. However, it is possible to test phase to

V1

V2 V3 Vf

I2

I3

- f

V’2 V’3


phase faults by modifying the fault voltage amplitudes only, provided that the zone limit is very close to the nominal setting, and amplitude changes do not exceed 5%: if they are more, also phase angles must be computed and changed. Other important note is that fault amplitudes of the two phases should be adjusted to the same value: different values cause a phase error between the phase to phase voltage and the fault current. This is particularly true when the phase to phase voltage tends to zero: in this situation, minor amplitude errors cause the complete loss of control on fault angle. For these reasons, it is not advisable to perform phase to phase fault tests unless with fault voltages of 5 V or more. In general, it is advisable to use the third generator, the one not involved in the fault, to measure the phase to phase fault voltage. Last but not least, the phase arrangement of fault voltages is not the same as pre-fault voltages. This means that we have to compute the voltage to current fault angle, and the angle between pre-fault voltage and fault voltage. In conclusion, given the fault impedance Z and the test angle f , we have to perform the following steps: . Select the fault current If; . Compute the fault voltage Vf (it is the phase to phase voltage!); . Compute the module of phase fault voltage VX; . For both phases, compute the angle f X of the fault voltage with respect to the fault current (that is in phase with the power supply); . For both phases, compute the angle of the healthy voltage with respect to the power supply. 1) Fault current The current will be adjusted on the two faulty phases (1 and 2; 2 and 3; 3 and 1), while the other remains at zero; its value is the one selected by the operator (for instance, 10 A). 2) Phase to phase fault voltage The phase to phase voltage is: Vf = Z*If*2 For instance: If = 10 A Vf = 20 * Z; with Z = 1 Ohm, Vf = 20 V. 3) Phase fault voltage For both faulty phases, the phase fault voltage is: VX = 0.5* sqrt(VN^2 + Vf^2) For instance, if Z = 1 Ohm; If = 10 A; Vf = 20 V; VN = 57.8 V, VX = 30.58 V The third phase does not change its amplitude, equal to VN.


4) Phase angle We will compute first of all the angle of fault voltage with respect to the voltage when the fault amplitude is zero, f X1, that is: f X1 = atg(Vf/VN) Given this angle, the following table summarizes the pre-fault angle and the fault angle for all types of test.

FAULT 1-2 2-3 3-1 V1 30°-f 0° -30° -f V2 -30° -f 30°-f 0°

FAULT ANGLE

V3 0° -30° -f 30°-f V1 - (60° - f X1) 0° 60° - f X1 V2 60° - f X1 - (60° - f X1) 0°

PRE-FAULT ANGLE

V3 0° 60° - f X1 - (60° - f X1) In our instance, f X1 is 19°; if f = 75°, phase angles to be programmed are the followings.

FAULT 1-2 2-3 3-1 V1 -45° 0° -105° V2 -105° -45° 0°

FAULT ANGLE

V3 0° -105° -45° V1 - 41° 0° 41° V2 41° - 41° 0°

PRE-FAULT ANGLE

V3 0° 41° - 41° These values apply for the test of the zone having the impedance of 1 Ohm ; for other zones they should be repeated. This made clear, the other thing to make clear is how to perform the test. Once all values are correctly programmed and adjusted, start the test: the relay will trip in zone N or in zone N+1. To check the setting, in the first case you need to increase Vf until the relay trips in zone N+1; in the second case you should decrease Vf until the relay trips in zone N. Once this is obtained, the zone setting is computed based upon the average of two Vf voltages that make the relay to trip in the different zones, Vf1 and Vf2: Z = (Vf1 + Vf2) / (4 * If)

V2 V3 Vf

f X1

V’3


The approximation is that we change only fault voltages and not the corresponding angle: the drawing explains the approximation. If the fault voltage needs to be increased more than 5%; else, also phase angles must be computed and changed. In our example, at first test the relay trips in zone N, with Vf = 20 V; on next test (higher voltage) the relay trips in zone N+1, with Vf = 20.5 V; then: Z = (20 + 20.5) / (4 * 10) = 1.012 Ohm.

1.12.7 Three phase fault In single phase faults, voltage and current vectors are modified during the test as shown in the following figure.

VR N

VR

VT V

S

VT N

VS N

−ϕ IR

IS

IT

As test starts, all voltages are modified from VN to Vf; the three fault current should be injected at the same time. This is not completely true with the three T/1000 because of the zero crossing feature: the three phases have zero crossings that are time shifted by 6.66 ms. The following figure explains the situation; this means that in first zone the trip time will be increased by 13,3 ms.

V2 V3 Vf1

V’3 Vf2

V’2


1) Fault current The current will be adjusted on all the faulty phases; its value is the one selected by the operator (for instance, 10 A). 2) Healthy voltages phase angles Choose the test angle in the R-X plane. If the distance relay is set on the CT star point towards Busbar, the angle F (I-V) has the same value but negative, otherwise it has the same value. These angles are adjusted prior to actual zone testing, as follows. Start the test; adjust the fault current; adjust the fault voltage at 30 V. Now select on all T/1000 the auxiliary Vac phase with respect to the current, as follows: AUX VAC/DC > Aux Vac control > Phase > Reference: current ESC This adjustment will not be modified during tests. 3) Zone limits test Given the fault impedances Z1, Z2, Z3, Z4 of the zone limits, compute as follows the corresponding fault voltages V1, V2, V3, V4: Vf = Z*If For instance: If = 10 A Vf = 10 * Z These voltages are the limits between following zones, as with the other faults. Once fault current and pre-fault voltage amplitudes have been adjusted to VN, stop the test and start again. Adjust all fault voltages at a value slightly less than V1, VT31: the trip time should be the one of zone 1. Slightly increase the fault voltages and start again with value VT32: trip time should become T2. The procedure can be repeated at will, until the first zone is checked with the desired accuracy: the result is Z1 = (VT31+VT32)/(2*If)

6.66 ms

PHASE 1

PHASE 2

PHASE 3


Once a limit has been found, repeat the test for other zone limits. During these tests, current and phase are no more modified. Example. Let us assume that the distance relay to be tested has the following settings at line angle (75°). ZONE LIMIT ONE TWO THREE STARTER IMPEDANCE Ohm

0.2 0.4 1 2

TIMING s

0.05 0.3 0.6 1.2

Let us assume: IV0 = 2.5 A; VN = 57.8 V (100 V). Maximum test current is: IMAX = 57.8/2 = 28.9 A. We choose If = 8 A; the corresponding zone limit voltages are: V1 = 1.6 V; V2 = 3.2 V; V3 = 8 V; VSTART = 16 V. We adjust all currents to 8 A; the V-I phase angle is -75° (line side) or 105° (Busbar side); fault voltages are 1.6 V. We start the test at 1.5 V; if trip time is 0.05 s we slightly increase all voltages and start again, until trip time becomes 0.3 s: let us assume that VT31 is 1.55 V and VT32 is 1.65 V. This means that first zone limit is 0.2 Ohm; the error is zero. If instead with 1.5 V the trip time is 0.3 s we reduce all voltages and start again, until trip time becomes 0.05 s: let us assume that VT31 is 1.4 V and VT32 is 1.5 V. This means that first zone limit is 0.181 Ohm; the error is -9%. The test continues with the following fault voltages, until all limits are tested.


1.13 TEST OF CONVERTERS There are many types of converters: current; voltage; power; power factor; frequency. The most common converter has a DC current output; the amount of current is proportional to the parameter, given the conversion factor. For many of these converters, the zero value corresponds to 4 mA; this value must be subtracted to the measured one prior to convert it into the measured parameter. The following connection scheme shows the connection of current, AC voltage, DC voltage to the converter, and the connection of the converter output to the low range DC current measurement input of T/1000. This scheme applies to converters having a conversion error of 2% up. For more accurate tests, you need a reference converter. In this instance, connect both converters (currents in series; voltages in parallel), and measure the error between the current of the converter under test and the reference converter.

The test procedure is simple: . Firs of all, supply the converter and measure the zero input current (nominally 4 mA). . Next, select values to be generated; compute the corresponding current measurement, and prepare a calibration table. . Next, generate the selected parameters, measure the reading, report it to the table and compute the converter error. For instance, you want to test a current converter with the following characteristic: I0 = 4 mA; I100 = 20 mA. From this, the nominal output current as a function of the input current is: Iout = 4 + Iin * (20-4)/100 = 4 + 0.16 * Iin You can prepare the following table:


TEST CURRENT

A NOMINAL MEAS.

mA ACTUAL MEAS.

mA ERROR

% 0 4 10 5.6 20 7.2 50 12 100 20


1.14 TEST OF ENERGY METERS Energy meters can be single phase or three phase; in the second case, with three or two equipments. As T/1000 is a single phase generator, it is possible to test single phase meters, or three phase with three or two equipments, provided that voltages are connected in parallel and currents in series. The following connection scheme shows the connection of current, AC voltage, DC voltage to the energy meter under test, and also to a sample meter. This scheme applies to all classes of energy meters, the accuracy range being given by the sample meter. For less accurate tests, class 2 or more, it is possible to avoid the use of the sample meter.

Each meter has its conversion constant, say Ks and Kt respectively for the sample meter (Ks) and for the meter under test (Kt). To perform the test: . Place a suitable sensor in front of the LED (or rotating disk) of the meter under test, and connect its output to the STOP input. If the meter outputs a voltage impulse or a relay contact the sensor is not necessary. . Define the nominal test energy EN. . Select the desired test voltage, current and phase angle, V, I and angle (power factor). . Define the nominal test time, TN = EN / (V*I*pf): it should be large enough to avoid that time measurements error influence the test result (more than 10 s). . Define the corresponding number of impulses N = EN / Ks. . Press ON and adjust current, voltage, angle to the desired values. Press OFF. . Select on T/1000 the COUNT mode; program a number of impulses equal to N: TIMER START/STOP > Stop > Count (N) ESC . Select the measurement of the generated energy: METERS > Other internal > Ea – Er ESC . Read on the sample meter counter the starting number of impulses, N1. . Press ON+TIME: current and voltage are applied until N+1 complete inputs are detected; at that moment, current generation ends and the corresponding time is displayed. The energy applied to both meters is taken from the sample meter, reading the number of impulses after the test, N2. The applied energy is: Es = (N2 – N1) * Ks.


The energy Et measured by the meter under test is read on the display. The error of the meter under test is E% = (Et – Es) * 100 / Es ON + TIME START COUNT 0 1 2 N-1 N TEST TIME If the sample meter is not available, the test is performed as follows. . Place a suitable sensor in front of the LED (or rotating disk) of the meter under test, and connect its output to the STOP input. If the meter outputs a voltage impulse or a relay contact the sensor is not necessary. . Define the nominal test energy EN. . Select the desired test voltage, current and phase angle, V, I and angle (power factor). . Define the nominal test time, TN = EN / (V*I*pf): it should be large enough to avoid that time measurements error influence the test result (more than 10 s). . Define the corresponding number of impulses N = EN / Ks. . Press ON and adjust current, voltage, angle to the desired values. Press OFF. . Select on T/1000 the COUNT mode; program a number of impulses equal to N: TIMER START/STOP > Stop > Count (N) ESC . Select the measurement of the generated energy: METERS > Other internal > Ea – Er ESC . Press ON+TIME: current and voltage are applied until N+1 complete inputs are detected; at that moment, current generation ends and the corresponding time is displayed. The energy applied to the energy meter under test, Es, is read on the T/1000 display. The energy measured by the meter under test is computed as follows: Et = N * Kt The error of the meter under test is: E% = (Et – Es) * 100 / Es NOTE. If it is desired to wait some turn prior to start the energy measurement, it is possible to connect the impulse input to both START and STOP input. Then, on START select COUNT and program the number of turns before the measurement; on STOP program COUNT and the number of test turns N.


1.15 TRANSFORMER DIFFERENTIAL RELAY TESTING WITH D/1000

1.15.1 Introduction This test is performed taking advantage of the option D/1000, that allows performing the following tests of differential relays: • Characteristic curve test; • Harmonic restraint. Before proceeding with the test description, we give some basic hints on differential transformer protections.

1.15.2 The transformer

There are many ways for connecting the transformer primary and secondary windings; they are classified as vectorial group.

§ IA is the primary current phase 1

§ Ia is the secondary current phase 1 Depending on the connections of winding 1 and 2 and the polarity, the vectorial groups are as follows:

• Yy0 – Yy6 • Dy1 – Dy5 – Dy7 – Dy11 • Yd1 – Yd5 – Yd7 – Yd11 • Dd0 – Dd2 – Dd4 – Dd6 – Dd8 – Dd10

A perfect test would require the use of 6 output currents; however, as T/1000 + D/1000 can generate only two currents, and only in phase, only a single phase test can be performed.

CONNECTION DAB CONNECTION DAC

Ia

IA 30°

13030

30==

−= aA IIG

ϕϕ

A

B

C c

b

a

n N


The setting of the differential relay is computed by computing the transformer taps, that are the Ipu (per unit current) after the CT on both HV and LV sides, when the transformer is at full load. The transformer TAPs are calculated according to: the nominal power Pn, the primary and secondary voltage V1n and V2n, the CTRatio, and the nominal current In:

n

n

ICTRVP

Tap***3 11

1 = n

n

ICTRVP

Tap***3 22

2 =

These values are the p.u. nominal current at relay level after the CT. They are fundamental when calculating the test currents to apply to the relay.

1

1 *3 VP

I n= 2

2*3 V

PI n=

1

11

"

CTRI

I = 2

22

"

CTRI

I =

Let’s give an example.

1.15.3 The Restraint and the Differential current We define IR as Restraint current and it is normally given as the average between current I1 and I2, where:

• I1: transformer primary side pu current • I2: transformer secondary side pu current

Depending on the relay manufacturer, the Restraint current is calculated as: • 21 III R += : this formula is used by Siemens relays

HV side LV side

Nominal Power 50 MVA 50 MVA

V nom 138 kV 24 kV

CT primary 250 1500

CT secondary 1 1

CT ratio 250 1500

Connection ? Y

Tap 0,837 0,802

Nominal currents on HV and LV side

AV

PI

N

NP 209

10*138*310*50

*3 3

6

11 === A

V

PI

N

NP 1202

10*24*310*50

*3 3

6

22 ===

… the relative current after the CTs are:

ACTR

II P

S 837.0250209

1

11 === A

CTRI

I PS 802.0

15001202

2

22 ===

837.01837.0

1

11 ===

N

S

II

Tap 802.01802.0

2

22 ===

N

S

II

Tap


• 2

21 III R

+= : this is the standard formula

• 3

21 III R

+= : this is used by some of GE relays for three windings transformer

• 21 III R ×= : this is used on Ret316 relays The differential current is defined as: 21 IIId −= A typical nominal characteristic of a transformer differential relay is displayed in the figure above. Testing the relay means to check the characteristic curve.

1.15.4 Connection to the relay First of all we have to determine the connection schematic. Assumptions:

• Group: YY0 • Tap 1 = 1 • Tap 2 = 1

A simple test can be performed in a very simple way.

• T1000 generates current I1 connected as displayed above. • D1000 generates current I2. • A1 is the internal measure of T1000. • A2 is the External measure of T1000 . The test principle is that we apply the restraint current to two inputs, primary and secondary, of one phase of the differential relay, while we apply the differential current only to one side. The connection scheme is the following.


The following is the D1000 front panel. There are two pairs of sockets: IN and OUT. IN is to be connected to the VCAUX output of T1000; D1000 converts the voltage into current, and generates the differential current, that is measured prior to connection to the relay. So, when we say that the differential current is to be adjusted, this means adjusting the auxiliary voltage.


The direction of the current is indifferent: on one direction, ID adds to IR; on the other one, it subtracts. With this arrangement, the test result is quite accurate, as we measure ID directly, rather than finding it from I1 – I2, as this implies being sensitive to the measurement errors of I1 and I2. The followings are the test steps. • Power-on T/1000, acting on switch (2): the internal light turns on. • Set the current adjustment knob (6) and the voltage adjustment knob (20) completely counter-

clockwise. • If you wish to use the DC voltage output to supply the relay under test, use knob (20) to adjust

the voltage value, that is displayed on the LCD display (23). Connect the DC supply input of the relay to sockets (63).

• Connect the I1 and I2 inputs of the relay to the two main current output sockets (13) that correspond to the current IR to be generated. For the sake of accuracy and ease of adjustment, select the smallest range greater that the maximum test current.

• Connect the TRIP output to the STOP input. • Select the connection socket measurement pressing the push-button (57): the LED turns on. This

enables current output measurement. WARNING: if you do not select the output socket, the test displays false current or voltage values.

• Connect the auxiliary voltage output sockets (62) to D/1000 IN sockets: D/1000 converts the applied voltage into a corresponding output current.

• Connect D/1000 OUT sockets between IN and one of the differential relay inputs (I2 in the figure), passing through the T/1000 external current measurement sockets (67): by doing so, the differential current, generated by D/1000, is metered.

• Select ON and check if you can too easily adjust the desired current, acting on knob (6). If the maximum test current is reached with a rotation less than one fifth of the total, this means that the burden is very low. In this instance, reduce the output power with the following menu commands:

Test control > Test power > 60 VA > ESC The 60 VA LED turns on. Select ON again, and check that the desired current can be reached with ease of adjustment; if the current is not reached, go back and select 300 VA.

• Set the save function, as follows. Test control > Save > Confirm at trip > ESC

• Set the timer with the following selections: Timer start/stop

START > INT (RET) STOP > EXT > Clean (Voltage) (RET)

Edge ESC NOTE: select stop clean or voltage according to the relay trip contact connections. • Set the external current measurement (that is ID) as follows.

Meters > External I > Enabled > 10 A ESC

1.15.5 Characteristic curve test Let us assume that the characteristic curve to be tested has the shape displayed in the figure. We take it just as an example. NOTE: the maximum value for ID is 5 A; if the highest setting of the curve is greater than 5 A, that part of the curve will not be tested.


As the curve is of the type parameter versus parameter, all its points are the result of a threshold test. The area below the characteristic is the no trip zone; the area above is the trip zone. 1st test The trip time is independent upon test parameters; so, it will be measured in a first test, as follows. • With I1 = 0, press ON and increase the auxiliary voltage acting on the knob (20) until the relay

trips: the fist point is found, as it is the differential current when the restraint current is minimum; test values are:

§ Restraint Current: 22

0

222 IIII

I BAR =

+=

+=

§ Differential Current: 2IIII BAD =+= NOTE: it is impossible to test the point with IR = 0, as IR is a function of Id. • Now increase slightly the current, and press OFF. Press now ON+TIME: the delay is the relay

trip time. Also this result can be saved. Reduce ID to a value less than the threshold. This procedure serves also to verify that all connections are correct. 2nd test The trip time is independent upon test parameters; so, it will be measured in a first test, as follows. • Slightly increase I1, press ON and increase the auxiliary voltage acting on the knob (20) until

the relay trips: another point is found and can be saved as the 2nd point of the curve:

§ Restraint Current: 2

*22

)(

221211 IIIIIII

I BAR

+=

++=

+=

§ Differential Current: 2211 )( IIIIIII BAD =+−=−=

Other tests Continue the same way as for test #2, in order to record as many points (IR-ID) as desired.

1.15.6 Displaying the characteristic with X-Pro 1000 First of all, transfer to the computer all records stored in the memory of the T1000. The parameter involved in the test are Iac and Ext I… you can show them directly in the software… or edit a formula

1: Select Formula 1

2: Select Ext_I

3: And click this button


by clicking the Formulas button and edit IR = (2*Iac+ExtI)/2 as Formula #1.

The relative graph could be as follows… not too bad for a manual test:

4: Edit the Formula 1

5: and confirm


1.15.7 Connections for different transformer connections Here below the connections for the most common situations.

FAULT TYPE Connection Phase 1 Phase 2 Phase 3

YY0

YD1

YD11

DY1

DY11

Beware of the following. § When you test relays for Yd or Dy Transformers, since the test is performed in single phase

mode, a v3 = 1.732 coefficient is to be applied on the current flowing in the Y connected pole. For a Yd transformer, the Restraint and Differential Currents formulas are the following:

o Restraint Current: 2

)(3

23

211 II

II

I

IB

A

R

++=

+=

o Differential Current: )(33

211 II

II

II B

AD +−=−=

§ Therefore, applying current Iac only (from T1000) may result in a trip even when the current

generated by the D1000 is zero: you must increase D1000 current until the relay contact drops out


§ If transformer Taps have to be taken into account, the above formulas become a little more complex:

o Restraint Current: 2

)(

32

3 2

21

1

1

21 TapII

Tap

ITap

I

Tap

I

I

BA

R

++

=

+

=

o Differential Current: 2

21

1

1

21

)(

33 TapII

Tap

ITap

I

Tap

II BA

D

+−=−=

1.15.8 Second harmonic restraint test This test requires that you generate a distorted waveform:

-1.5

-1

-0.5

0

0.5

1

1.5

0 0.005 0.01 0.015 0.02 0.025

50 Hz 2nd Harm 50 Hz + 2nd Harm

The only way to generate such current waveform is the following: § Generate the fundamental using Iac output from main generator of T1000; § Set 100 Hz on Aux Vac output; § Connect Aux Vac output to D1000; § Connect D1000 output in series to the measuring input 10 A of the T1000; § Connect the two output currents in parallel.

Test procedure: § Connect the two currents to the relay input; § Increase Iac until the relay trips; § Then increase Aux Vac to increase the current from D1000… until the relay trip drops out.

Take note of the two values and calculate the 2nd Harm %

• H%: the harmonic percentage is 100*_

_22%

IExtIac

IExtH

+=


2 USER’S GUIDE

2.1 HAZARDOUS SITUATIONS The following table lists a number of situations that are potentially hazardous to the user and/or to the test set. Please consider this list, and check the situation in case of doubt. SITUATION CAUSE OF RISK CONTROL TEST SET NOT GROUNDED

Capacitor dividers take the case at 110 V. The unit is not protected against common mode noise

Ground connection

Voltage (or current) neutral connected to ground

The test set ground and the neutral ground are connected to very distant points of the grid. There is a voltage differential between the grounds; in case of fault, there is an heavy risk for the test set and for the operator

VN (IN) connected to ground

Filtered mains The AC voltage can be a squared waveform rather than

sinusoidal; the test set operates at the minimum supply level, with low efficiency.

Supply waveform

Connection to a live wire The connection can be dangerous to the user, to the test set and even the plant.

Test before connecting

Long generation of all outputs

Possible danger of over-heating components, specially with high ambient temperature

Check burden and duration

Of these points, the first two are very hazardous, both for the user and the test set. THESE TYPES OF FAULT ARE NOT COVERED BY THE WARRANTY. For the first hazard, the connection of the test set to any metal frame connected to ground solves the problem. The second hazard does not apply if the relay to be tested is not connected to the plant. If, instead, the connection to the relay is performed by means of a test connector (or directly to terminal blocks), the operator must be sure that fitting the test connector interrupts the connection to the ground. This is normally true; however, we experienced some instance were this was not performed. The problem in this instance is that VN of P.T.’s (or IN of C.T.’s) is connected to ground in a point of the grid that is far away (sometimes very far away) from the control building. Between the ground of the test set and the ground of P.T.’s there is a voltage differential that is caused by eddy currents; in case of ground fault, this voltage grows to very hazardous levels, for both the user and the test set. Checking it is simple: just test with a resistance meter that there is no connection between VN or IN and the ground.

2.2 CONNECTION TO THE RELAY AND POWER-ON At first, be sure that the main control knob (6)is turned (rotated) to the zero position (complete counter-clockwise). The reason is that the current generator is actually a high current voltage


generator. If the output is connected to the load (typically low impedance), as soon as the test is started, a very high current can circulate in the circuit. Next connect the mains supply cable to the instrument and then to the supply. THE SUPPLY VOLTAGE MUST BE THE SAME AS INDICATED ON THE PLATE. Power-on T-1000: a diagnostic sequence controls: . Key microprocessor board components; . Auxiliary supply voltages. If something is wrong, the operator is alerted by a message. At the end of it, default selections are active; T-1000 is in the OFF state. Perform the first selections, according to the type of relay to be tested: . Main output socket, acting on the selector push-button (57). . Auxiliary AC voltage: range; type of generation; value. . Auxiliary DC voltage: range; value. . Start and Stop timer inputs. Connect the relay to be tested to the output sockets that have the indication light (LED) on. The following is the list of protections that avoid damaging T-1000 in case of errors. . Fuse on the mains supply. . Thermal NTC sensor on the main and auxiliary transformers. In case of over-temperature, an alarm message is displayed. . Thermal sensors on the SCR that controls current injection, and of the internal temperature. In case of over-temperature, an alarm message is displayed.

2.3 TEST CONTROL The T-1000 front panel is explained in next paragraph. T-1000 generation is controlled by the two keys < (55) and > (56). Settings and menu selections are controlled by the multi-function knob with switch (22): see next paragraph for menu selections description. At power-on T-1000 generation is OFF, as confirmed by LED (50). The ON selection serves for finding relay thresholds; selections ON+TIME and OFF+TIME serve to measure relay timing. The following flow diagram summarises all available test control selections.

TEST CONTROL

Test mode Fault injection

Normal (default) Trip + pulse time Reclose mode

Maintained Momentary Timed External OFF delay

1 period 8 periods Save min

Test power Save

Save max

Don’t save Automatic at trip Confirm at trip Manual Auxiliary contact


The performance of T-1000 in Normal Test mode is the following. . OFF: main outputs are not generated; Vac aux is generated, and it can be either the pre-fault value or the fault value, according to selections; Vdc aux is generated. In this condition, any trip of Stop input is ignored. . ON: timer starts; main outputs are generated; Vac aux has the fault value; Vdc aux does not change. In this situation any trip at Stop input is detected; it is possible to verify and memorize the relay threshold, both trip and reset. As the relay trips, the TRIP LED (43) turns on for 5 seconds; during 5 seconds, parameters at trip are displayed; then, the standard measurement is restored. Test results can be saved according to Save selections. . From OFF to ON + TIME: main outputs are generated and the timer starts according to selections; as Stop trips or resets, T-1000 returns to OFF, the TRIP LED (43) turns on and parameters at trip are displayed until ON or ON+TIME are selected. Test results can be saved according to Save selections. . From ON to OFF + TIME: main outputs are removed the timer starts according to selections; as STOP is sensed, T-1000 returns OFF, the TRIP LED (43) turns on and parameters at trip are displayed until ON or ON+TIME are selected. Test results can be saved according to Save selections. Other test mode selections: . Trip + pulse time: the timer measures the delay and the duration of the trip impulse. . Reclose test. It is possible to select via menu the test of a reclosing scheme. In this operating mode T-1000 automatically applies current as soon as the RECLOSE command is sensed at START input. The test set measures and stores the trip delay and the delay between trip falling edge and RECLOSE trailing edge (see figure 4). Maximum number of Reclose commands: 49; maximum test commands for all Reclose commands: 9999 s.


FAULT 1 2 TRIP (STOP) 1 2 RECLOSE (START) 1 2 TIME MEASUREMENTS D1 R1 D2 R2 Other Fault injection selections: . Maintained (default): .. ON mode: fault outputs are generated until OFF is selected. .. ON+TIME or OFF+TIME: as the STOP input is sensed, T-1000 returns OFF. . Momentary: in ON mode, main outputs are generated until the > push-button is pressed; . Timed: in all modes (ON; ON+TIME; OFF+TIME), fault outputs are generated for the programmed maximum time; after this, T-1000 returns OFF. Any trip after this time is not sensed. . External. This mode allows for the synchronization of more T-1000: they start generating upon reception of the START input, that is selected in External mode. . OFF delay: fault parameters can be maintained for the specified time after relay trips: this allows simulating the circuit breaker delay. Test power selection: it allows reducing the available power; this increases the adjustment sensitivity for low current tests on low burden relays. Save selections: . No automatic saving. . Automatic test data saving as relay trips. A pop-up window confirms the saving and tells the test number. . Test data can be saved after confirmation. After relay trip, pressing the multi-function knob the operator can save the test result. . Manual test data saving. This selection can be used any time: it serves if the trip is confirmed by a light and not by a contact. Test data selections. Data to be saved can be measured the following way: . One period before the trip: this is the standard selection for timing measurement, and for threshold test, provided that trip time is not long; . Eight periods before the trip (less if eight are not available): this is used in case of unstable test results due to waveform distortion; . Save the minimum period within 0,5 s before trip: this is used for high threshold measurement, when the timing is long; . Save the maximum period within 0,5 s before trip: this is used for low threshold measurement, when the timing is long. Auxiliary contact delay: the switch of the auxiliary contact can be timed with respect to test start.


2.4 CURRENT GENERATION If the following current limits and time duration of main current outputs are trespassed, the generation is interrupted, and the operator is warned by an alarm message. 1) MAXIMUM POWER 300 VA RANGE

A AC CURRENT OUTPUT

A

MAXIMUM POWER

VA

LOAD TIME

s

RECOVERY TIME

min 30 300 STEADY - 50 30 min 100 75 600 45 100 800 60 15 150 3 10

100

250 1000 1 5 12 300 STEADY - 20 30 min 100 30 600 45 40 800 60 15 60 3 10

40

80 1000 1 5 5 400 STEADY -

7.5 15 min 45 10 800 60 15 15 5 10

10

20 1000 2 5 2) MAXIMUM POWER 60 VA RANGE

A AC CURRENT OUTPUT

A

MAXIMUM POWER

VA

LOAD TIME

s

RECOVERY TIME

min 30 60 STEADY - 38 10 min 45 53 60 10

100

70 0.75 2 12 60 STEADY - 17 10 min 45 23 60 10

40

36 1 2 5 60 STEADY - 6 10 min 45 7 60 2

10

10 1,5 2 This generator serves for the test of current, power, directional, distance relays, where current or current and voltage are necessary. The procedure is the following.


. At first, be sure that the main control knob (6) is turned (rotated) to the zero position (complete counter-clockwise). . Power-on T-1000. . Select by the push-button (57) the measurement on the desired output sockets (13), according to the maximum current to be generated: the LED turns on; the AC voltage value is displayed. . Connect the relay to be tested to sockets (13). Consider that for tests of 40 A up it is necessary to connect the relay by a wire having at least a cross section of 10 sq. mm; for lower currents, a cross section of 2.5 sq. mm can be used. . Press ON and adjust the output current to the desired value with knob (6). . After you have started the test, if the burden is a short circuit made of a short cable, you measure at zero knob position a current that usually is less than 3% of the range. This value does not influence at all the measurement of the current you are generating: it is not an error of the measurement instrument. If the current is a problem, select the 60 VA power, and/or connect resistors in series. . There are two more possible problems: the desired current cannot be reached; the adjustment is difficult because the current is reached too easily. .. If it is impossible to reach the desired value, this is because the burden is too high. Very often the problem comes from connection wires; so, to perform the test it is necessary either to shorten them, or to increase the cross section (or both). .. If the adjustment is reached within 1/5th of the knob rotation, then it is possible to increase the ease of adjustment by reducing the test power as follows. TEST CONTROL > TEST POWER (Power) ESC .. It is also possible to increase the ease of adjustment by connecting a resistor of the set in series to the relay. Resistors are rated 50 W; so, compute the resistance value as follows: (RESISTANCE) = 50 / (TEST CURRENT)^2 Maximum test current values are resumed here below. RESISTANCE 0.5 1 22 470 1000 2200 MAX ITEST 10 7 1.5 0.3 0.2 0.15 Note that the test starts and stops as the current passes the zero.

2.5 AC VOLTAGE GENERATION FROM MAIN OUTPUT If the current of 3.5 A is exceeded on main AC voltage output, the generation is interrupted, and the operator is warned by an alarm message. This generator serves for the test of synchronism relays, where two voltages are necessary. The procedure is the following. . At first, be sure that the main control knob (6) is turned (rotated) to the zero position (complete counter-clockwise). . Power-on T-1000. . Select by the push-button (57) the measurement on output sockets (60): the LED turns on; the AC voltage value is displayed. . Modern relays have a burden that is negligible: the burden is mainly caused by the connection wires. If high test currents are to be generated, use connection wires with a suitable cross section: 10 sq. mm for 40 to 100 A tests (short time); 2.5 sq. mm. for lower currents. There are two possible situations:


.. Power is not enough; the desired test current cannot be adjusted. If this occurs at high currents, the problem is that the burden is too high; the solution is either shortening wires or increasing their cross section (or both). .. Power is too much: the desired current is reached with a little movement of knob (6). This is the case with low test currents. If the knob movement is less than 1/5th of its span, it is possible There are two ranges available: 250 V at 300 W continuous (full power); 57 V at 60 W continuous (reduced power). The default at power-on is full power; if 57 V are enough, for a better adjustment, reduce the power as follows. TEST CONTROL > TEST POWER (Power) ESC . Adjust the output voltage to the desired value with knob (6). . Connect the relay to be tested to sockets (60). Check that the adjusted voltage does not drop as you connect the relay; else, this would mean that T-1000 is overloaded (or that you are connecting to a live wire). In this situation, remove the cause of error and connect again.

2.6 DC VOLTAGE GENERATION FROM MAIN OUTPUT If the current of 3.5 A is exceeded on main DC voltage output, the generation is interrupted, and the operator is warned by an alarm message. This generator serves for the test of timers and all devices that are driven by a DC voltage. The auxiliary DC voltage generator cannot be used to this purpose as it is continuously generated: no time measurement can be performed. To this purpose, act as follows. . At first, be sure that the main control knob (6) is turned (rotated) to the zero position (complete counter-clockwise). . Power-on T-1000. . Select by the push-button (57) the measurement on output sockets (61): the LED turns on; the DC voltage value is displayed. . There are two ranges available: 300 V at 300 W continuous (full power); 68 V at 60 W continuous (reduced power). The default at power-on is full power; if necessary, reduce the power as follows. TEST CONTROL > TEST POWER (Power) ESC . Adjust the output voltage to the desired value with knob (6). . Connect the relay to be tested to sockets (61). Check that the adjusted voltage does not drop as you connect the relay; else, this would mean that T-1000 is overloaded (or that you are connecting to a live wire). In this situation, remove the cause of error and connect again.

2.7 AC VOLTAGE GENERATION FROM THE AUXILIARY OUTPUT The auxiliary AC voltage is protected by an electronic circuit that stops the voltage generation and opens the connection to outputs socket in case of overload (short circuit included). In case of intervention, an alarm message is displayed. Via the control knob the operator can reset the alarm and close the relay to restore operation. The auxiliary AC voltage is also protected by a thermo switch that intervenes in case of over-heating. In case of intervention, an alarm message is displayed. The auxiliary AC voltage is used to test relays that need voltage and current at the meantime. In this situation, the voltage is continuously generated; usually, it is adjusted to the nominal value, and it is


not changed during all tests. It is possible to phase shift the current with respect to voltage; selections are the following. . Power-on T-1000: the AC voltage value is displayed. . There are three ranges available: 65; 130 or 260 V AC; the power is 30 W continuous; 40 W peak for 1 minute. For increased power and accuracy, it is better to select the range that is closest to the value to be generated. The default at power-on is 65 V; if necessary, select the desired range. The operating mode is pre-selected as Fault: do not change it. Do not change also the pre-selected frequency, as Locked to mains. Last, set the desired current phase angle; however, to perform this, T-1000 must be ON, and some current must circulate. Selections are performed as follows. AUX VAC/VDC > Aux Vac control > Range > (Range) RET Phase > Reference: current > (Phase) ESC This performed, adjust the voltage to the desired value with knob (20). Eventually, connect the relay to be tested to sockets (62). Check that the adjusted voltage does not change or the overload message pops up as you connect the relay; else, this would mean that T-1000 is overloaded (or that you are connecting to a live wire). In this situation, remove the cause of error and connect again (reset the alarm if it popped up). Execute the test, modifying the phase angle as necessary. This output is also used for the test of voltage relays, frequency relays, synchronism relays; frequency rate of change relays. In these instances, it is necessary to use the Pre-fault + Fault selection. This feature allows adjusting two different values: the pre-fault voltage, that simulates the situation prior to fault, and the fault voltage. The pre-fault voltage adjustment is performed by the control knob, while knob (20) adjusts the fault value. Voltage output selection is automatic: pre-fault voltage with test stopped; fault voltage with test started. The switch from a value to the other one is performed without falling to zero. The main current or voltage is generated at the zero crossing; the fault one is generated at the meantime of main voltage or current. The selection of the reference is performed automatically, following the selection of main output measurement. If the main DC voltage is selected the reference is taken on the main AC voltage. MAIN AC CURRENT (MAIN AC VOLTAGE) AUXILIARY VOLTAGE TEST START The Pre-fault + Fault selection is performed as follows. AUX VAC/VDC > Aux Vac control > Mode > Pre-fault+Fault > Pre-fault amplitude ESC


Once the nominal voltage is adjusted to the pre-fault value, it is possible to change the amplitude (V, SYN relays) or frequency (F, SYN relays), or angle (SYN relays: in this instance, the angle is referred to V main rather than to I main) or frequency rate of change (dF relays) of the fault voltage. The pre-fault (nominal) frequency is always the mains one; the fault one is adjusted by the control knob, in the range 40 Hz to 500 Hz. Switching from nominal frequency to fault frequency is performed without altering the output voltage amplitude and phase. The frequency adjustment is performed as follows. AUX VAC/VDC > Aux Vac control > Frequency > Adjust > (Frequency value) ESC The angle adjustment is performed as explained above; the difference is that the adjustment is applied only when T-1000 is ON; with the instrument OFF, the pre-fault voltage is normally in phase with the current. It is also possible to phase shift the pre-fault voltage with respect to the fault voltage. This parameter is necessary during the test of distance relays, when phase to phase faults are simulated: as test starts, the auxiliary voltage changes amplitude and phase with respect to the pre-fault value. V1 PRE-FAULT V1 FAULT FAULT ANGLE V1 FAULT

PRE-FAULT ANGLE I1 FAULT V2 V3 The pre-fault angle adjustment is performed as follows. AUX VAC/VDC > Aux Vac control > Mode > Pre-fault+Fault > Phase (phase) ESC This angle is referred to the fault voltage; so, for its adjustment is not necessary to have T-1000 ON. Last, it is possible to test frequency rate of change relays, by setting both the starting frequency, as before, and the frequency ROC range, with range from ± 0.01 to ± 99.99 Hz/s. The frequency change stops at 40 or 70 Hz. The frequency ROC adjustment is performed as follows. AUX VAC/VDC > Aux Vac control > Frequency > Adjust > Frequency ROC (ROC) ESC As test starts, the frequency goes to the pre-set frequency, and from that value starts increasing or decreasing with the pre-set ROC.

2.8 DC VOLTAGE GENERATION FROM THE AUXILIARY OUTPUT The auxiliary DC voltage is protected by a current limiter. The user notices the low voltage and removes the overload. The fuse protects the case of counter-feed.


The second auxiliary generator can be used to supply the auxiliary DC voltage for the relay to be tested. To this purpose, the voltage is continuously available at sockets (63). Use this generator as follows. . Power-on T-1000: the DC voltage value is displayed. . There are two ranges available: 130 or 240 V DC; the power is 90 W. For increased power and accuracy, it is better to select the range that is closest to the value to be generated. The default at power-on is 130 V; if necessary, select the desired range as follows. AUX VAC/VDC > Aux Vdc control > (Range) ESC This performed, adjust the voltage to the desired value. Eventually, connect the relay to be tested to sockets (63). Check that the adjusted voltage does not change as you connect the relay; else, this would mean that T-1000 is overloaded (or that you are connecting to a live wire). In this situation, if it is not a connection error, it is possible to reduce the voltage until the voltage does not drop: relays tolerate a wide range of DC supply voltages.

2.9 AUXILIARY CONTACT - The auxiliary make and break contact, closes (opens) at test start, and opens (closes) as current is cut off after the STOP input is sensed. Maximum time error between current and make/break contact: 1 ms. - The contact can also be used to simulate the circuit breaker state. Maximum error between current start after the trip command and make/break: 1 ms. - Possibility to delay the auxiliary contact switch with respect to test start. Delay range: from 0 to 99.99 s. - Contacts range: 5 A; 250 V AC; 120 V DC

2.10 THE TIMER Timer inputs are protected against wrong selections. If the voltage free input is selected and a voltage is applied less than 250 V ac or 275 V DC, circuits will not be damaged. The auxiliary contact is protected by a re-triggering fuse: if it trips, remove the source of the problem and then restore it. Characteristics of Start and Stop inputs: . Inputs do not have any common point, and are opto-coupled from the instrument at 1.35 kV AC; . Inputs connection: two banana sockets per input; . Type of input: either clean or under voltage; maximum input: 250V a.c or 275 V DC; . Inputs may be independently selected as Normal Open or Normal Close or Edge: the latter means that the timer is stopped by any transition; . Selections are displayed on the front panel by 10 dedicated lights; . For both inputs, when the input is closed or with voltage an LED turns on; . When the relay intervenes the TRIP light turns on.


The timer offers a number of possible selections to permit many different types of testing depending on the selection by the operator. The following flow shows all possible selections. The default selection is the following. . Timer start: internal; as test is started. External start allows synchronizing more T-1000. . Timer stop: external. Internal stop means that the timer is stopped as T-1000 goes OFF. With this selection, the timer meters the elapsed time between START and STOP. Alternative selections: .. Elapsed time plus the duration of STOP input; the selection is performed as follows: TEST CONTROL > Test mode > Trip + pulse time ESC .. Impulse counting:: this mode is foreseen for the test of energy meters. Maximum input frequency: 10 kHz; voltage threshold can be set as for tripping. It is possible to select this mode via menu, and to set the number of impulses; the test set measures the time corresponding to the set number of complete periods applied to STOP input after ON and during all generation, and measures the corresponding energy (if selected). The selection is performed as follows: TIMER START/STOP > STOP > External > Count > (number of counts) ESC If the count is selected on START, time measurement will be performed after the set number of counts has expired: this serves to pass the start-up of the energy meter. Input thresholds. When the contact has voltage applied, two thresholds can be selected. The low setting applies to nominal voltages of 24 and 48 V; the high setting to 110 V up. The selection is performed as follows: TIMER START/STOP > STOP > External > Clean-voltage > Voltage threshold ESC Time can be metered as seconds or cycles (second is the default). The selection is performed as follows: TIMER START/STOP > Units > s or Cycles ESC

2.11 FINDING RELAY THRESHOLDS

2.11.1. Introduction There are different types of relay characteristic curves: time depending or independent; single threshold or multiple thresholds. Let us consider the following example, that applies to an overcurrent relay with a time-dependent curve and one (or more) time-independent threshold. Of this relay we want to find and save trip and drop-off I> and I>> thresholds.

TIMER START/STOP

Start Stop

Timer

Internal External

Clean-voltage N.O.-N.C.-Edge Count

Internal

External

Clean-voltage N.O.-N.C.-Edge

Unit s (default) cycles

Count


. Set the “Automatic save at trip” function, as follows. Test control > Save > Confirm at trip > Save min > ESC NOTE: for other selections see the pop-up menu chapter. . Set the timer with the following selections: Timer start/stop > START > INT (RET)



211.2. First threshold trip and drop-off The first session is finding threshold I>, that is the limit between no trip and trip (with long delays). NOTE: with any other type of single-threshold the relay, the procedure is the same. . Select ON; slowly increase the current. . As the relay trips, pressing the multi-function knob tripping values can be saved. Confirm save results pressing the multi-function knob, and proceed. Next, we find the drop-off threshold for I>. . First, change the Test control settings as follows. Test control > Save > Confirm at trip > 1 period > ESC . From the trip current above, slowly decrease the current; as the relay resets, save test result.

I (I/IN)

t

I> I>>

t>>

(t>) tmax


2.11.3. Second threshold trip and drop-off

The second session is finding threshold I>>. The problem is that the test result criterion is no more to find the limit between no trip and trip; it is instead to find the limit between two different timings: what we have shown as t>, for currents less than I>>, and t>> for currents more than I>>. There are many ways to perform the test; we suggest taking advantage of the Timed generation option, as follows. . Set the “Don’t save” function, as follows. Test control > Save > Don’t save ESC . Start from a current more than I>; select ON+TIME, and check for time response. Increase the test current, repeat the test until the relay trips with a delay t>>. Reduce the current, and take note of the timing t>. Compute tmax as 80% of t>. . Set the Save function, and Timed test, as follows. Test control > Fault injection > Timed > tmax (RET)

Save > Confirm at trip > 1 period > ESC . Select ON; increase the current starting from a value less than I>>. If the relay trips within tmax, pressing the multi-function knob tripping values can be saved; if not, the test goes OFF with no message. In this instance, select ON again until you find the trip. Confirm save results pressing the multi-function knob, and proceed. NOTE: this procedure applies to any multi-threshold relay, including distance relays. For these latter relays, as the Impedance vs. time curve has increasing steps (more delay for higher fault impedance) the limit will be found setting a fault voltage (at the given current) and then decreasing it. Next, we find the drop-off threshold for I>>. . Press ON from the trip current above. . Slowly decrease the current; as the relay resets, pressing the multi-function knob tripping values can be saved.

2.12 FINDING RELAY TIMINGS After having measured the threshold of the relay, in the manner stated before, it is possible to measure the intervention time of the relay. Relevant timings are: trip and drop-off delays; they can be tested on over-current (voltage, frequency..) relays, or on under-current (voltage, frequency..) relays. Available test selections are: . Over-current relay trip delay: from OFF to ON+TIME; . Over-current relay drop-off delay: from ON to OFF+TIME; . Under-current relay trip delay: from ON to OFF+TIME; . Under-current relay drop-off delay: from OFF to ON+TIME. All these tests are performed after having pre-adjusted the desired test current (or set of parameters).


I

t

5A) Overcurrent relay trip delay

5B) Undercurrent relay trip delay

I

t

Stop

Stop

FAULT

FAULT

Trip delay

Trip delay

Let us consider for example the timing test of an over-something relay, where the trip contact is Normal Open. The test is performed as follows. . First thing, select the Maintained fault injection, as follows Test control > Fault injection > Maintained (RET) . Set the “Automatic save at trip” function, as follows. Test control > Save > Confirm at trip > 1 period> ESC NOTE: for other selections see the pop-up menu chapter. . Set the timer with the following selections: Timer start/stop > START > INT (RET)

STOP > EXT > Clean (Voltage) (RET) NO ESC

. Now, press ON and pre-adjust the first set of fault parameters: as the relay trips, don’t save test result; go OFF. . Select ON+TIME: as the relay trips, test goes OFF; pressing the multi-function knob tripping values can be saved. The TRIP LED (43) turns on and parameters at trip are displayed until ON or ON+TIME are selected. Confirm save results pressing the multi-function knob, and proceed with other test currents, until all points to be tested are measured. Now we can measure the drop-off timing. . First thing, select the NC level for the relay reset contact: Timer start/stop > STOP > EXT > Clean (Voltage) > NC ESC


. Now, press ON and pre-adjust the same set of fault parameters.

. Select OFF+TIME: as the relay resets, pressing the multi-function knob drop-off values can be saved. Confirm save results pressing the multi-function knob, and proceed. With different test values, other timings can be measured.

2.13 BASIC TEST PRINCIPLES

2.13.1. Introduction In the years many different types of protection relays have been developed: . With different technologies (electromechanical, solid state, microprocessor); . Different ways of setting the same values; . Other performances (multiple thresholds, conditioning signals). Testing relays allows a wide range of different modes to get the same result; so, for the first thing the user must choose the type of test to be performed. The easiest type of test is to check the settings. In this instance it is sufficient to generate the relevant parameters (voltage, current, angle) with values close to the settings. With two timing tests, little below and little above the settings, it is possible to test that they are correct, within a specified tolerance. For instance, testing an over-current relay set at 10 A can be performed with two delay tests: at 9.5 A (-10%) the relay should not trip; at 10.5 A (+5%) it should trip; also the timing can be tested. A more complex and complete test is the control of the complete characteristic curve of the relay. There are two types of characteristic curves: - Parameter vs. time: it displays the trip time as the parameter changes. Examples are: current vs. time, for an over-current relay; impedance vs. time for a distance relay. It is understood that for currents less than the threshold, or for impedances higher than the general starter, no trip occurs. - Parameter vs. parameter: they display the trip limit of a parameter vs. another one; other variables are kept constant. For example, the current vs. voltage curve of an earth fault relay, that applies for a given range of phase shifts. Other examples: P vs. Q curve for a reverse power relay; R vs. X curve for a distance relay; R vs. X curve for a loss of field relay. The key difference between these types of curves is that the first one can be tested with timing tests, while the other one is a collection of threshold tests, where one of the variables is kept constant. As a consequence, the first type of curves is easily tested, with a multiple delay test; the second one requires an analysis of the shape of the curve.

2.13.2. Parameter vs. time characteristic As an example of the parameter vs. time curve, we consider the characteristic curve of a time-dependent overcurrent relay.


t

I

t>>

I> I>> I-t over-current relay curve The curve means that: . If the test current is less than I> no trip occurs; . For current more than I> and less than I>> trip time is a function of the test current; . For currents more than I>> the trip time is t>>. This curve can easily be tested by selecting ON+TIME tests at increasing test currents. The user can decide how many tests to perform to reach the desired confidence that test results match with the nominal curve.

2.13.3. Parameter vs. parameter characteristic As an example of the parameter vs. parameter curve, let us consider the characteristic curve of an earth fault directional relay. First of all, the curve applies only if the test is executed at given angles between current and voltage. Then, at these angles, the curve means that for current and voltages below it there is no trip, while above it the relay trips. In the curve the trip time is not shown, yet this is the parameter to be measured in order to understand if we are below or above the curve. This means that each point of the curve is a threshold limit between trip and no trip; the threshold can be found moving one parameter and keeping the other one constant. However, we must be careful before executing the test.

V

IIminVmin

A

B


I-V directional relay curve For instance, in order to find the point A it is apparent that the procedure is: . Set the voltage; . Increase the current until the relay trips. However, in order to find the point B the best procedure is: . Set the current; . Increase the voltage until the relay trips. In fact, if we search the point B threshold keeping constant the test voltage, a minor error on the voltage would cause a big error on the current. The same problem would occur testing point A at constant current. The test of this relay should be split in two: constant voltage for the first half; constant current in the second half. In conclusion, when we perform the test we should consider who does the variable parameter move on the characteristic plane, and avoid asymptotic situations. As a second example of the parameter vs. parameter curve, consider the following curve: it is the general starter of some type of distance relays.

The area to the right is the trip zone; to the left it is the no trip zone. The test strategy should be the following: . For points A, B, D: set the test voltage and increase the current until the relay trips; . For point C, set the test current and decrease the voltage until the relay trips As third example we can study the problem of testing a loss of field relay, that has the following characteristic.

V

I

A

I V 0

V M I N

V N

I V N

B

C

D


X

RA

B

CD

The area of intervention is the one within the circle with the centre in the negative X axis. The first problem is to convert R and X into the corresponding V, I, angle; then, the current is set at IN, and only voltage and phase are modified. The test is performed as follows: . For point A, set the angle at 180°, start from V=0 and increase V until the relay trips; . For point B, set the angle at 180°, start from V higher than the setting and decrease V until the relay trips; . For point C, set for V the average of A and B, start from an angle greater than 270° and reduce it until the relay trips. In a similar way, for D, start from an angle smaller than 270° and increase it until the relay trips.

2.14 USE OF THE TEST SET AS A MULTIMETER The test set can be used as a powerful multimeter, as it allows measuring: . Voltage, AC and DC; . Current; AC and DC; . Frequency; . Impedance and its components; . Power (active, reactive, apparent, power factor); . Phase angle: with respect to the mains or between two inputs. This feature allows also to check the outputs generated by the test set itself. The marking CAT II means that these inputs are suitable for the measurement of voltage or currents connected to the mains. It is important not to exceed the maximum ratings, as marked. The low current input is protected by a fuse; all other inputs are not protected: if the rating is exceeded, this could cause the permanent fault of the corresponding input. . Prior to the measurement, enter the MENU selection, and enable the display of the parameter you desire. . For the measurement of voltage or current, just connect to the corresponding input. . The frequency is measured only on the voltage input: connect it and select the F measurement. . The measurement of the impedance or of the resistance of a component fed by an external source is performed as follows.

.. Open the circuit, and connect the component to the external current measurement;


. Connect the component terminals to the external voltage measurement: this avoids errors caused by the connection leads and by the current measurement circuit; . Select the desired measurement (Z+ f , or R+X); . Close the circuit, taking care not to exceed the current limits. The measurement does not change as soon as current and voltage are high enough: this confirms the correct measurement.

. For power measurements of an external source proceed as follows. .. Open the circuit, and connect the component to the external current measurement; . Connect the component terminals to the external voltage measurement: this avoids errors caused by the connection leads and by the current measurement circuit. Take care not to exchange leads, otherwise the power will be displayed with a negative sign; . Select the desired measurement (P, Q or S, p.f.); . Close the circuit, taking care not to exceed the current limits: the measured power is displayed.

. For phase angle measurement, first of all select if you want to measure the angle of your current or voltage with respect to the mains, or current with respect to voltage. NOTE: if one of the values is low, the measurement with respect to the mains is more stable. Then, connect the voltage or current (or both), taking care of the positive sign, that must be connected to the red socket: the measured angle is displayed. The following table summarizes the available measurements. N. PARAMETER , AC INPUTS DERIVED

FROM FORMULA UNITS

ACTIVE POWER, P Iext, Vext; f P= I*V*cos (f ) W 1 REACTIVE POWER, Q Iext, Vext; f Q= I*V*sin(f ) VAr APPARENT POWER, S Iext, Vext S= I*V VA 2 POWER FACTOR, p.f. f p.f. = cos(f ) -

3 IMPEDANCE, Z and f Iext, Vext, f Z = V/I Ohm, ° ACTIVE IMPEDANCE COMP., R Iext, Vext; f R = Z* cos(f ) Ohm 4 REACTIVE IMPEDANCE COMP., X Iext, Vext; f X = Z* sin(f ) Ohm

5 FREQUENCY, F Vext - Hz PASE ANGLE, IE TO V2 F , IE-V2; ref. V2 - ° 6 PASE ANGLE, VE TO V2 F , VE-V2; ref. V2 - °


3 TEST SET AND POP-UP MENU

3.1 THE FRONT PANEL

RS232

A

0

0.5 1 22

1000 4702200

100

10A 7A 2.15A

0.15A 0.22A 0.33A

0.7A300VA

60VA

ON+TIME

OFF OFF+TIME

ON MENU

SEL

isaT1000

RELAY TEST SET

24

23

6

25 2163 19 120

56

55

50

49

52

51

22

42

41

43

2

8

48

47

343133 32 3637 39 40 3835 65 18 5366 54 6760 6164 68

13

45

44

46

57

62

+-

V

250V

Ω

The following list includes the key components inside T/1000; see the schematic on last page. 1) Main supply fuse, rated T10A, incorporated in the supply socket. 2) Power-on switch. 3) Transformer for the auxiliary voltage outputs. 4) Transformer for the auxiliary supplies. 5) Main outputs transformer. 6) Main outputs adjustment. 7) INTE ON-OFF printed circuit board; code YWA11400. 8) Earth socket. 9) Auxiliary DC voltage board; code YWA11395. 10) Auxiliary AC voltage amplifier; code YWA11396. 11) Back panel board ; code YWA11399. 12) Output current measurement transformer. 13) Output sockets for main current output.


14) Auxiliary voltage amplifier output transformer. 15) Microprocessor board code YWA41300. 16) Converter board code YWA11401. 17) Front panel board; code YWA11398. 18) Auxiliary contact protection re-triggering fuse, rated 5 A. 19) Auxiliary DC voltage fuse, F2A. 20) Adjustment of auxiliary AC voltage output. 21) Adjustment of auxiliary DC voltage output. 22) MENU control knob, with switch. 23) Display. 24) Resistors set. 25) Serial interface connector. 31) Internal START selection light. 32) Normal Open START selection light. 33) Normal Closed START selection light. 34) Under voltage START selection light. 35) Voltage clean START selection light. 36) Internal STOP selection light. 37) Normal Open STOP selection light. 38) Normal Closed STOP selection light. 39) Under voltage STOP selection light. 40) Voltage clean STOP selection light. 41) START input closed or with voltage light. 42) STOP input closed or with voltage light. 43) TRIPPED condition recognized light. 44) 100 A range selection light. 45) 40 A range selection light. 46) 10 A range selection light. 47) 300 VA (normal power) selection light. 48) 60 VA (reduced power) selection light. 49) ON + TIME light: current is generated and time metered until STOP is detected. 50) OFF light: no current generation. 51) ON light: current is generated. 52) OFF + TIME light: current is removed and time metered until STOP is detected. 53) Main AC voltage selection light. 54) Main DC voltage selection light. 55 and 56) START and STOP push-buttons. 57) Push-button for the selection of main output. 60) Main AC voltage safety sockets. 61) Main DC voltage safety sockets. 62) Auxiliary AC voltage sockets. 63) Auxiliary DC voltage safety sockets. 64) Sockets for the connection to the external Start input. 65) Sockets for the connection to the Stop input. 66) Auxiliary Normal Open and Normal Closed contacts. 67) External current meter safety sockets. 68) External voltage meter safety sockets.


3.2 DISPLAY AND CONTROL LIGHTS At power-on, the following control lights turn on (default situation): . START: INT (31); NO VOLTAGE (35); . STOP: NORMAL OPEN (37) and NORMAL CLOSED (38) (EDGE selection); NO VOLTAGE (40); . TEST OFF (50); . MENU SELECTION: 100 A SOCKET (44); . POWER: 300 VA (47). These lights change according to program selections. At power-on and during the standard operation the display shows the measurements of: main AC current (or main AC voltage or main DC voltage, according to selection); auxiliary AC voltage; auxiliary DC voltage; elapsed time. To the left is the area for the access to the menu selection. Still at power-on, the auxiliary AC voltage is available at sockets (62), and can be adjusted with the knob (20). Also the auxiliary DC voltage is available at sockets (63), and can be adjusted with the knob (21). When the menu is accessed, the measurements are displayed without the headings. If some further measurement is selected (external measurements, power..) they are displayed below the menu, and only while the menu is not accessed.


3.3 THE POP-UP MENU The following is the list of features that are menu selected. The menu is operated by means of the control knob marked MENU, that incorporates a switch. The menu is entered pressing the knob and selecting the item moving the knob. Once the item has bee found and programmed, pressing the arrow the menu moves back of one step, so that other programming can be performed; else, selecting ESC the menu returns to the main window. During this operation the display shows output measurements, in reduced format. After confirmation, menu messages disappear, and measurements are displayed in the standard format. Any setting can be saved to and recalled from the memory. Up to 10 settings can be stored and recalled; setting no. 0 is the default one, and pops up at power-on. Settings are permanently stored in the memory; new settings can be written to the same address after confirmation. For normal mode operation it is possible to recall the standard setting, that cannot be modified. During the test, test results can be stored in the memory (up to 500 results may be stored). At the end of test, settings and test results can be transmitted to a PC provided with TDMS. The software allows saving test results, examining them and so on. The specification of TDMS is given in a separate document. When the PC is connected, settings can also be created and transferred into T-1000 using TDMS. The flux diagram of menu selections can be found in Appendix 1.


LEVEL1 LEVEL 2 LEVEL 3 LEV. 4 FUNCTION

Normal (default) Measures the time delay from START (internal, external) to STOP (internal, external).

Trip + pulse time Measures the time delay from START (internal, external) to STOP (internal, external), and the duration of STOP.

Test mode

Reclose mode

TD; No. reclose

Two delays are measured: fault to STOP; STOP to START (reclose command). At START, a new fault is generated after TD (0-999.99 s), until the number of reclose (max 49) is reached.

Maintained (default) Generation lasts indefinitely Momentary Generation lasts until the ON button is pressed External Generation starts upon reception of the START

input: this allows synchronising T/1000. Timed Max time Generation lasts for the pre-set time duration. Max

time 999 s.

Fault injection

OFF delay

T delay The main output OFF is delayed by the set amount of time or cycles.

Output power

300 VA (default) – 60 VA

Selection of full (300 VA) or reduced (60 VA) power

Don’t save (default) Test data are not saved Automatic, at trip As relay trips data are saved to the next memory

location Confirm, at trip As relay trips data can be saved, after confirmation

Save

Manual When selected, generated values are saved.

TEST CONTROL

Auxiliary contact

Timing Sets the contact timing with respect to test start


LEVEL 1

LEVEL 2

LEVEL 3

LEVEL 4

FUNCTION

INT (default) Timer starts when ON or ON+TIME are activated and outputs generated.

NO-NC-EDGE

After ON or ON+TIME, timer starts on the external input. External START input Normally Open, or Normally Closed, or Both (EDGE).

CLEAN-24 V – 80 V

After ON or ON+TIME, timer starts on the external input. External START input without or with voltage. If with voltage, two voltage thresholds are available: 24 or 80 V.

Start

EXT

COUNT Timer enters the counting mode; it is possible to program the number of transitions prior to time measurement. After ON or ON+TIME, the test set waits for these transitions before measuring the time.

INT Timer stops when the current of the main generator is interrupted.

NO-NC-EDGE (def.t)

Timer stops when the STOP input is detected. External STOP input Normally Open or Normally Closed or Both (EDGE).

CLEAN-24 V – 80 V

Timer stops when the STOP input is detected. External STOP input without or with voltage. If with voltage, two voltage thresholds are available: 24 or 80 V.

Stop

EXT (def.t)

COUNT Timer enters the counting mode; it is possible to program the number N of transitions to be detected. After ON or ON+TIME, the time from the first valid input to input N+1 is measured; the corresponding energy can be read on the display.

s (default) Time duration metered in seconds

TIMER START/ STOP

Timer cycles Time duration metered in cycles


LEVEL 1

LEV. 2

LEV. 3

LEVEL 4

LEVEL 5 FUNCTION

Range 65 (default) ; 130 ; 260 V. Fault (default)

The auxiliary AC voltage is adjusted by the dedicated knob, and is always present, independently by test start. If the auxiliary voltage should be applied along with the main current or voltage, go to next selection.

Prefault Amplitude

Sets the pre-fault auxiliary AC voltage amplitude. Entering this selection in OFF mode the pre-fault voltage is immediately generated: pre-fault voltage is generated and displayed, and adjusted by the multi-function knob. NOTE: the fault voltage is generated pressing ON or ON+TIME, and it is adjusted as usual by the knob.

Prefault Phase (0..359°)

Sets the pre-fault auxiliary voltage phase with respect to the fault voltage; the angle is adjusted by the multi-function knob. The pre-set value is not metered.

Prefault duration

Sets the duration of the pre-fault auxiliary voltage. When ON or ON+TIME are pressed, the pre-fault will be generated at the mains frequency for the selected duration; then the fault voltage is generated, at the programmed frequency.

Mode

Prefault + Fault

Prefault frequency

The prefault frequency of the auxiliary voltage may be programmed. The selected frequency is applied when outputs are OFF.

Locked to mains (default)

If “Locked”, the auxiliary voltage is at the mains frequency.

Adjust freq 40-500.000 The frequency of the auxiliary voltage may be programmed. Frequency changes at test start; output voltage does not change in amplitude.

Frequency

Adjust r.o.c.:

± 0.01.. 9.99 Hz/s

The frequency ramps at the programmed rate of Change. The starting frequency can be the mains or the value set by adjust freq.

Locked to mains(default) With this selection Vaux is in phase with the mains. Adjust phase Vaux - mains

The fault auxiliary voltage can be phase shifted with respect to the mains. The measured angle is displayed. Test must be ON; for a correct angle measurement, the auxiliary voltage must be more than 20% of the range. Phase is adjusted by the multifunction knob.

Adjust phase Vaux – I main

The fault auxiliary voltage can be phase shifted with respect to the main current. The measured angle is displayed. Test must be ON; for a correct angle measurement, current and voltage must be more than 20% of the range. Phase is adjusted by the multifunction knob.

Aux Vac control

Phase

Adjust phase Vaux – V main

The fault auxiliary voltage can be phase shifted with respect to the main voltage. The measured angle is displayed. Test must be ON; for a correct angle measurement, both voltages must be more than 20% of the range. Phase is adjusted by the multifunction knob.

AUX VAC/ VDC

Aux Vdc control

Range 130 V (default) or 240 V. If this selection has to be changed, it’s necessary to adjust the voltage output to the minimum by the dedicated knob.


LEVEL1 LEVEL

2 LEVEL 3 LEVEL 4 FUNCTION

Normal If selected, current values are displayed in A.

Units of I

I/IN IN If selected, displayed values are defined as I/IN, that can be defined.

Normal If selected, voltage values are displayed in V.

Internal

Units of V

V/VN VN If selected, displayed values are defined as V/VN (phase voltage), that can be defined.

AC (default) - DC

With selection AC the meter performs the true rms measurement; with selection DC, the measurement is performed on the average.

10A – 20 mA Selects the current input socket

External I

Enabled

Waveform If selected, the current waveform is displayed

AC (default) - DC

With selection AC the meter performs the true rms measurement; with selection DC, the measurement is performed on the average.

Shunt : 1 – 1000 mOhm If the voltage is coming from a current dropping on a shunt, specifying the shunt value the current is displayed; default 100 mOhm.

METERS

External V

Enabled

Waveform If selected, the voltage waveform is displayed


LEVEL1 LEVEL

2 LEVEL 3 FUNCTION

None (default) No extra measurement displayed Active power P; W Reactive power Q; VAr Impedance module Z, Ohm Impedance argument f , ° Active impedance component

R, Ohm

Reactive impedance component

X, Ohm

Apparent power S; VA Power factor p.f. = cos(f V-I) Active energy (AC) Ea; Wh

Other internal

Reactive energy (AC) Er; VArh None (default) No extra measurement displayed Active power P; W Reactive power (AC) Q; VAr Impedance module Z, Ohm Impedance argument f , ° Active impedance component

R, Ohm

Reactive impedance component (AC)

X, Ohm

Phase, I (AC) f , Vmain-Iext; reference Vaux Phase, V (AC) f , Vmain-Vext; reference Vaux Apparent power (AC) S; VA Power factor p.f. = cos(f V-I) Frequency of V (AC) f, Hz

Active energy (AC) Ea; Wh

METERS (continued)

Other external

Reactive energy (AC) Er; VArh Note: measurements marked AC apply only if both inputs are selected as alternate current.


LEVEL1 LEVEL 2 LEVEL 3 LEVEL 4 FUNCTION

Selected result(s) RESULTS Delete All results

Save to address 1..10 Saves current settings to X Restore address 1..10 Restores settings from X

Settings

Restore default 1..10 Restores default settings Language UK, FR, SP, PT, GE, IT Select the desired language

Slow The displayed value is refreshed every 1000 ms

Speed

Fast The displayed value is refreshed every 300 ms

Hold trip As relay trips, test data measured 4 periods before trip are held.

Hold min As relay trips, the minimum value within 0.5 s is held.

Display

Hold mode

Hold max As relay trips, the maximum value within 0.5 s is held.

CONFIGU- RATION

LCD Contrast

It allows to adjust the LCD contrast


4 THE HELL, IT DOESN’T WORK

4.1 INTRODUCTION Sometimes, when my ears whistle, I wonder if it is because of some of my customers being angry at us because the test set doesn’t work: according to Murphy’s law, when it was most necessary. We at ISA do our best efforts to filter the so-called infant mortality of electronic components prior to delivery of all our test sets; and this after extensive testing of prototypes and pre-production units. Yet, sometimes faults occur, because everything dies, including electronic components; so, please, before shooting at us, see if the following instructions can serve you to fix the problem. If not, e-mail us the problem, not forgetting to mention the unit’s serial number: our business is to minimize your downtime. My e-mail address is: [email protected] Last, our experience is that our test sets withstand very heavy duty cycles for long wiles, if correctly used; most problems arise because of: . Lack of grounding in the mains supply; . Voltage or current neutral is connected to earth; . Severe spikes on the mains (spikes are not always so kind to respect standard limits); . Transit, with the associated drops and thermal cycling; . Errors, such as the connection to live wires, or generating current on a short circuit with the handle completely turned to the maximum current. Please mention in your e-mail how did the fault occur: this serves us for our continuous improvement program.


4.2 ERROR MESSAGES The test set performs a number of tests at power-on and during the generation. The following table lists all the messages, and the corrective action. A) TESTS AT POWER-ON (and runtime) ERROR MESSAGE CONSEQUENCE CORRECTIVE ACTION + 15 V supply failure If the error is not confirmed it

is possible to continue; else, the test cannot proceed

Try some power on – off; if persists, three steps: . Check the fuses; . Try to replace the CONV board; . Return the test set.

- 15 V supply failure If the error is not confirmed it is possible to continue; else, the test cannot proceed

Try some power on – off; if persists, three steps: . Check the fuses; . Try to replace the CONV board; . Return the test set.

NVM access If the error is not confirmed it is possible to continue; else, the test cannot proceed

Fault in the MICR board: replace it

B) RUNTIME TESTS ERROR MESSAGE CONSEQUENCE CORRECTIVE ACTION 60 VA IAC supply time The test lasted too long; tests are

blocked for the specified duration Wait until the message disappears

300 VA IAC supply time The test lasted too long; tests are blocked for the specified duration

Wait until the message disappears

IAC while VDC supplied Generation is stopped The test set is sensing a burden both on main IAC and VAC or VDC, what is forbidden. Remove one of the burdens

MAIN VAC The main AC voltage is overloaded; generation is stopped

Reduce voltage or burden of main AC voltage

MAIN VDC The main DC voltage is overloaded; generation is stopped

Reduce voltage or burden of main DC voltage

AUXILIARY VAC The auxiliary AC voltage is overloaded; generation is stopped

Reduce voltage or burden of the auxiliary voltage

ERROR OVERLOAD RECOVERY xxx s

If you try to restart before the above message disappears, the test set informs you about the residual time

Wait until the message disappears

OVERTEMP POWER TRANSFORMER

Generation is stopped The main transformer temperature is too high because of heavy loads or very long test duration: wait until it cools down

OVERTEMP SCR’S HEAT

Generation is stopped The temperature of the SCR that drives the test is too high because of heavy loads or very long test


duration: wait until it cools down OVERTEMP T1000 ENGINE

Generation is stopped The test set temperature is too high because of heavy loads or very long test duration: wait until it cools down

4.3 TROUBLE SHOOTING The following table summarizes main faults, cause of fault and correction. When in the correction you find “see text”, please proceed with the following paragraphs. SYMPTOM POSSIBLE CAUSE CORRECTION Problems after transport Heavy shock Open T/1000 and check for

loose boards or connections At power-on does not turn on Mains supply fuse open

Other causes See text

After the general over-temperature alarm message it does not turn on

The power transformer was over-heated

Wait at least 30 minutes before trying again: it needs time to cool down.

The auxiliary DC voltage is not generated

The protection fuse was broken by a contact with a live wire. One protection fuse is blown

Replace fuse (19). Replace fuse on the fuses board. Replace fuses on the module (see text below)

The auxiliary contact does not close

The contact was over-loaded; the protection fuse tripped

Press on the retriggerable fuse (18).

It is impossible to measure on the 20 mA range

The input was overloaded; the PTC protection is not restored

Wait 15 minutes before trying again.

No generation of I main Damaged INTE ON-OFF See text No measurement of I main Broken connection See text Measurements are completely false

The microprocessor has lost its correction factors

Go to the calibration procedure and repeat it.

The display is dark Protection fuse blown See text Unstable auxiliary AC voltage measurement.

Fault of AC voltage generation circuit

See text

The TRIP input is not detected Damaged INTE ON-OFF See text Over-load alarm on the auxiliary AC voltage cannot be restored; AC voltage cannot be generated.

Fault of AC voltage amplifier. Contact your agent for support, detailing: . test set number; . how did it occur


4.4 PHYSICAL DESCRIPTION T/1000 components are accessed by removing the five screws that are located below it, and lifting the central part by the handles. There is a main board mounted on the front panel, and a number of components mounted on the back panel. The arrangement is shown in the figure below.

3 9

14 4

10

12

5

5

3

4


The picture above shows the base with the auxiliary DC and AC modules removed. The following picture shows the front panel with the big control board.

On the upper corner are mounted the control cards; their location is shown in the drawing below. Cards are kept in place by the piece of aluminium sheet on the right, and also by the threaded bar between the boards. If a board is failing, it is necessary to remove the two screws as shown, and to un-tighten the nut of the threaded bar, as shown; in case some component touches it, it is necessary to remove it.

INTE ( 7 )

CONV ( 16 )MICRO ( 15 )


The two parts set apart are shown in the following picture.

4.4.1 Protection fuses By the side of the boards support is mounted a board with a set of protection fuses. They protect the following modules: . Auxiliary DC voltage supply: timed 0.25 A; . Display back light: timed 1.6 A; . Internal supply + 15 V: timed 1 A; . Internal supply - 15 V: timed 1 A; . Internal supply + 5 V: timed 0.8 A; . Internal supply + 12 V: timed 1 A. The first one protects the auxiliary supply: if it is blown, there is no DC voltage output. The second one protects the DC to DC converter that feeds the LCD backlight: if it is blown, the LCD display is very dim, even if it is possible to see something. The other ones protect the supplies of electronic components: if they fail. All the test set cannot operate. 4.4.2 Auxiliary supplies


On the edge of the CONV board are mounted a number of ring-shaped test points. They carry the key auxiliary supplies, which operate the test set. The arrangement of the test points is the following.

0 V

+ 1 2V

+5V

+5V

+5V

+5V

0 V

0 V

+ 1 5V

- 1 5V


If any of these voltages is missing, the test set cannot operate: it is necessary to find out if it is a problem of blown fuse, or repair the auxiliary voltage circuit. 4.4.3 No power at power-on The mains fuse is located in the power supply plug, in the small drawer. Replace it. At power-on, almost no power (50 W) should be drawn from the mains. If the power is more, the most likely faulty component is the auxiliary DC voltage circuit; next, it is the auxiliary AC voltage circuit. To ascertain this, it is necessary to remove: . three connectors from the DC voltage generator: two bigger, white, one on the front, one on the rear, plus one flat cable; . Five connectors from the AC voltage amplifier: four white, mounted on top of the board, plus a flat cable. After this, power-on, and verify that the display operates, and that the LED’s on the front panel turn on with the default values. If so, re-insert the modules one after the other, in order to detect which one is faulty. In case of DC voltage generator, see here below what else to do; in case of the AC voltage amplifier, it should be replaced.

4.5 AUXILIARY DC VOLTAGE FAULT If the fault is on the DC voltage supply and fuse (19) is OK, it is possible that the fuse on the fuses board is blown, or that one of the fuses mounted on the board has blown up. In this instance, proceed as follows. . Open the test set, as explained above, and locate the fuse on the fuses board. Check it and replace if necessary. . If OK, locate fuses on the auxiliary DC voltage board (see picture below). . Check fuses and replace them if necessary. They are 20 mm long; F1 is F3.15A; F2 is F2A. . If a fuse is blown, replace it, power-on and check if the DC voltage is available. If it is OK, the fuse was weak; if it is not, there is a fault on the board, that needs to be replaced.


The last test is to remove the connector J800 coming from the big round power transformer. The connector has 4 pins: the voltage between pins 1 and 4 should be 155 V AC nominal; between pins 2 and 3 should be 11.5 V AC nominal. If this is correct, the module is faulty; else, the power transformer is faulty.

4.6 NO OUTPUT FROM THE MAIN CURRENT AND VOLTAGE This is the case when you can start the test, but no output is generated from the main current and voltage outputs. In this situation the fault is located in the INTE ON-OFF board (7), that is located in the boards pack. The replacement is very fast: just follow the instructions above for the opening of T/1000 and board replacement.

4.7 DOES NOT MEASURE THE MAIN CURRENT Remove T/100 from the container. Just below the output sockets there are two yellow wires going to a MOLEX-type connector; the other side of the connector has two wires soldered to the main board. These yellow wires are made of a single enameled wire coming from the secondary of the measurement transformer: it is possible that they broke just on the connector, and so you loose the measurement. The fixing is easy: just solder the wires to the connector, taking care to peel the enamel so that it can be soldered.

F1 F 3.15 A

F2 F 2 A


4.8 THE DISPLAY BACKLIGHT DOES NOT TURN ON The backlight is supplied by a DC to DC converter that is mounted on the main board, that is mounted below the front panel. If the backlight does not turn on, the converter is likely to be faulty. The converter replacement is performed as follows. . Remove T1000 from the container. . Go to the left side: the sketch below shows the main components. . The converter is mounted as shown in the design below.

. First of all, verify that the two-way, AMP type white connector is correctly fit, and that wires are not loose. . Next, try to re-solder the four connecting pins of the converter to the main board: we once had a case of poor soldering. . If this is not enough, it is necessary to replace the converter. To this purpose, it is necessary to replace the converter. To this purpose, we suggest to remove the faulty one by cutting pins as short as possible, so that cleaning holes is easier; then, solder the new converter.

FRONT PANEL

SPACERS

DISPLAY

DC TO DC CONVERTER

4 CONNECTING PINS

VARIAC


4.9 THE AC VOLTAGE MEASUREMENT IS NOT STABLE First of all, check that there is no unplugged connector or broken wire. Next, it is necessary to understand if the problem is in the measurement or if the output is actually unstable. To this purpose, connect the output to an AC voltage meter and verify the reading. If it is unstable as well, the problem is in the amplifier; otherwise, it is in the measurement circuit. In the first instance, amplifier, we have to verify if the problem comes from the adjustment potentiometer. To this purpose, proceed as follows: . Go to the menu and select PREFAULT + FAULT; . In the PREFAULT mode, the output voltage is adjusted by the multi-function knob, and not by the potentiometer: please verify the output. If it is stable, the problem is located in the adjustment knob. If it is unstable, it can be located on the AP/50 amplifier, or on the CONV board. The problem when replacing CONV is that, as it hosts the measurement circuits, after replacing it, it is necessary to repeat the calibration. It is up to you if you want to receive the replacement boards or to deliver the test set to us. In the second instance, the fault is in the measurement, we have to replace the CONV board, with the problem explained above.

4.10 THE TRIP INPUT IS NOT DETECTED OR TIMING ERROR When the voltage clean trip input is selected, a voltage of about 20 V DC can be measured on START or STOP inputs; when the contact closes, a current of about 10 mA flows though it and detects the contact status. If with this selection the closed contact is not detected, and 20 V are not applies, the fault is located in the INTE ON-OFF board (7), that is located in the boards pack. The replacement is very fast: just follow the instructions above for the opening of T/1000 and board replacement. If there is a doubt about the timing metered by T/1000, please proceed as follows. . First of all, go to the CONFIG selection; settings, and select RESTORE DEFAULT: this avoids that some exotic setting is the cause of the problem. . Next, connect a jumper to the STOP input. Start the ON+TIME test: the timer should display 0 to 2 ms. . Now, go to the TEST CONTROL selection, and to the AUXILIARY CONTACT. Set the timing of 10 ms. Connect the C, NO contacts of the auxiliary output to STOP inputs. Start ON-+TIME: it should display 10 to 12 ms. You can test more with different timings of the auxiliary contact.

4.11 PROBLEMS DURING UPGRADE If during the Upgrade operation the power went off, and the test set is no more operational, to recover the situation proceed as follows. - Remove (or unlock a little) the metal bar that fixes the two aluminium columns. - Remove the two connectors placed on the INTE board. - Remove the INTE board, and then the pack MICRO + CONV. - Open the pack MICRO + CONV. - Change the position of the mini-dip switch N. 8 on the CONV board (it is OFF; it must be set


ON). - Insert again all the boards (and the INTE connectors too). - Turn on the test set. - At this point , the instrument should be connect to your PC. Execute the firmware download. Verify that the new firmware version appears; if yes, you have to turn off and set the dipswitch N. 8 to OFF (as it was initially).

4.12 THE ENCODER IS BROKEN In this instance, it is necessary to have some skill and patience. The procedure is the following. . You have in your hands the new encoder: it must replace the faulty one. This means that you have to dismount the old one, unsolder the five wires going to it, solder them to the new one, mount it. . It is necessary to gain access to the faulty encoder. If you look at it, it is surrounded by other components: no access. It is necessary to remove the DC voltage generator board, and also to remove the variable transformer: remove the control knob, and dismount it removing the three screws below the knob. . Now you have room enough to operate. Remove the encoder: the five wires going to it are long enough to allow you keeping it in your hand. . Unsolder the first wire, and solder it to the new encoder, in the same position: with this procedure you are sure not to exchange wires. . At the end of soldering, mount back the new encoder, power-on and check that it is correctly operational. After this, complete the mounting of the test set.

4.13 THE FAULT CANNOT BE FIXED If the fault is too hard to be fixed, you have to deliver T/1000 back to your agent. We have encountered problems caused by a poor packing of instruments that have been delivered us for calibration or repair. In order to avoid such inconveniences, please apply the following procedure. First of all, compile the following form, and attach it to the instrument. Please do not forget to compile it. With the instrument should come the mains supply cable, and the serial interface cable. The user’s manual originally delivered with the test set is not necessary. Cover the instrument itself with a polyester film, in order to protect it against dust and foam. The instrument should be protected by anti-shock foam having a minimum thickness of 5 cm ON ALL SIDES. Use a new carton box as a container. On the box apply the UP and the FRAGILE labels. In the box the instrument will be placed horizontal or standing; not upside down. If the set is heavier than 20 kg it is better to use also a pallet: this ensures that the box will not be packed upside down. Last but not least, do not declare an high value for customs: this expedites clearance of the good and lowers fees.


INSTRUMENT RETURN FORM

DATE ____________ AGENT _________________ COUNTRY ___________________ TYPE OF INSTRUMENT ____________________ SERIAL NO. __________________ INSTRUMENT RETURNED FOR: CALIBRATION ____ REPAIR ____ In case of repair, please specify the following. DATE OF FAULT _______________ REPORTED BY E-MAIL, PHONE ___________ COMPANY _____________________ USER’S REFERENCE ____________________ FAULT DESCRIPTION ____________________________________________________ ________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________ HOW DID IT OCCUR ______________________________________________________ ___________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________ LOCAL ANALYSIS OR ATTEMPTS TO REPAIR _______________________________ ___________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________ RECOMMANDATIONS AND NOTES _________________________________________ ____________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________


4.14 CALIBRATION

4.14.1 Introduction T/1000 does not need to be calibrated, as metering circuits employ high stability components. It is suggested to check the unit every 3 years, by comparing T/1000 measurements to external meters. Tests should be performed with an high accuracy multi-meter, that should guarantee a maximum AC measurement error of 0.1%, both for voltage and current. Besides, as such multi-meters do not have current ranges greater than 2 A, for the test of the high current ranges it is necessary a class 0.1 measurement Current Transformer. The adoption of lower-class instruments may cause false interventions, that introduce errors into the test set. At the end of the test, if deviations are not acceptable it is possible to enter the calibration mode, as explained in the followings.

4.14.2 Calibration procedure The calibration mode is accessed by pressing push-buttons < and > at the meantime, and powering on T/1000. The windows that opens up allows for first selections. The operating mode is the following: . Select the range to be calibrated. Calibrated ranger are checked. . Set to zero the adjustment knob. . With no output, ad just the off-set. . Press > to go ON. The external meter measures the output; T/1000 displays its measurement. . There are two adjustment parameters: COARSE and FINE. Go to the COARSE adjustment, and modify it until the T/1000 measurement is greater than the one displayed by the external meter. Reduce the COARSE adjustment until T/1000 measurement is less than the external one; go to the FINE adjustment and modify it to the best match with the external meter (the difference should be less than 0.2% of the reading). . Press the multifunction knob to confirm. T/1000 continues to generate: it is possible to check that the measurements match. If necessary, it is possible to re-enter the same range and repeat the adjustment; else, go to the next range: T/1000 goes OFF. . Take now the output to the value to be tested, to verify for the linearity of the measurement. If the measurement has a negative error, go back to range adjustment, reduce the COARSE adjustment parameter and increase the FINE one. . Go to next range, and so on, until the calibration is completed. The program alerts if a scale is not calibrated. At the end of the session, all parameters are saved in the non volatile FLASH EPROM.


4.14.3 T/1000 output calibration The internal measurements calibration is performed by generating the following current and voltage outputs. For each output range there is a number of measurement scales, that are separately adjusted: during the use T/1000 automatically selects the best scale. This increases the measurement accur acy. The table lists two sets of values: the one to be generated during the calibration, and the one to be used for linearity. OUTPUT RANGE SCALE CALIBRATION

VALUE LINEARITY TEST

NOTE FOR OFF-SET CALIBRATION

1.999 A 1 A 2 A Current sockets open 10 A 19.99 A 10 A 20 A Current sockets open 0,799 A 0,5 A 0,8 A Current sockets open 7.999 A 5 A 8 A Current sockets open

40 A

79.99 A 50 A 80 A Current sockets open 19.99 A 10 A 20 A Current sockets open

Main current

100 A 199.9 A 100 A 250 A Current sockets open 1,999 V 1 V 2 V Voltage sockets shorted 19.99 V 10 V 20 V Voltage sockets shorted 199.9 V 100 V 200 V Voltage sockets shorted

Main AC voltage

250 V AC

299.9 V 200 V 280 V Voltage sockets shorted 1,999 V 1 V 2 V Voltage sockets shorted 19.99 V 10 V 20 V Voltage sockets shorted 199.9 V 100 V 200 V Voltage sockets shorted

Main DC voltage

300 V DC

399.9 V 200 V 400 V Voltage sockets shorted


OUTPUT RANGE SCALE CALIBRATION

VALUE LINEARITY TEST

NOTE FOR OFF-SET CALIBRATION

1,999 V 1 V 2 V Voltage sockets shorted 19.99 V 10 V 20 V Voltage sockets shorted 59.99 V 50 V 60 V Voltage sockets shorted

65, 130 V AC

199.9 V 100 V 100 V Voltage sockets shorted 1,999 1 V 1 V Voltage sockets shorted 19.99 V 10 V 10 V Voltage sockets shorted 59.99 V 50 V 60 V Voltage sockets shorted 199.9 V 100 V 100 V Voltage sockets shorted

260 V AC

299.9 V 200 V 200 V Voltage sockets shorted 65 V; 10 A 57 V; 5 A 130 V; 10 A 100 V; 5 A 260 V; 10 A 200 V; 5 A 65 V; 40 A 57 V; 12 A 130 V; 40 A 100 V; 12 A 260 V; 40 A 200 V; 12 A 65 V; 100 A 57 V; 30 A 130 V; 100 A 100 V; 30 A

Angle between Vacaux and Imain

260 V; 100 A 200 V; 30 A 65 V 57 V; 57 V 130 V 100 V; 57 V

Auxiliary AC voltage Vacaux

Angle between Vacaux and Vmain

260 V 200 V; 57 V

19.99 V 15 V 20 V No O.S. calibration 130 V

DC 149.9 V 100 V 150 V No O.S. calibration 19.99 V 20 V - No O.S. calibration 199.9 V 100 V 200 V No O.S. calibration

Auxiliary DC voltage 260 V

DC 299.9 V 200 V 300 V No O.S. calibration


4.14.4 T/1000 external measurements calibration The external measurements calibration is performed using T/1000 as the source. As for the measurement of internal parameters, for each input range there is a number of measurement scales, that are separately adjusted: during the use T/1000 automatically selects the best scale. This increases the measurement accuracy. The table lists two sets of values: the one to be generated during the calibration, and the one to be used for linearity. INPUT AC/DC RANGE SCALE CALIBR.

VALUE LINEAR. TEST

TEST NOTES

5 mA 5 mA - Use Vdc aux + 2200 Ohm 20 mA 25 mA 25 mA - Use Vdc aux + 2200 Ohm 1.99 A 1 A 2 A

DC

10 A 9.99 A 2 A - 4 mA 4 mA - Use Vac aux + 2200 Ohm 20 mA 20 mA 20 mA - Use Vac aux + 2200 Ohm 1.99 A 1 A 2 A 10 A 9.99 A 5 A 10 A 1.99 A 1 A; 57 V -

Current measurements

AC

Angle with respect to Vacaux

9.99 A 5 A; 57 V -

19,99 V 10 V 20 V 59.999 V 50 V 60 V 199.99 V 100 V 200 V

DC 600 V DC

599.9 V 300 V 600 V 19.999 V 10 V 10 V 59.999 V 50 V 60 V 199.99 V 100 V 100 V

600 V AC

599.9 V 300 V 300 V 1,99 V 1 V; 57 V - 19.999 V 10 V; 57

V -

199.99 V 10 V; 57 V

-

Voltage measurements

AC

Angle with respect to Vacaux

599.9 V 300 V; 57 V

-


5 CHARACTERISTICS The following is a summary of key test set characteristics; for the complete T/1000 specification, please refer to document SIE10093.

5.1 MAIN AC CURRENT 1) MAXIMUM POWER 300 VA RANGE

A AC CURRENT OUTPUT

A

MAXIMUM POWER

VA

LOAD TIME

s

RECOVERY TIME

min 30 300 STEADY - 50 30 min 100 75 600 45 100 800 60 15 150 3 10

100

250 1000 1 5 12 300 STEADY - 20 30 min 100 30 600 45 40 800 60 15 60 3 10

40

80 1000 1 5 5 400 STEADY -

7.5 15 min 45 10 800 60 15 15 5 10

10

20 1000 2 5 2) MAXIMUM POWER 60 VA RANGE

A AC CURRENT OUTPUT

A

MAXIMUM POWER

VA

LOAD TIME

s

RECOVERY TIME

min 30 60 STEADY - 38 10 min 45 53 60 10

100

70 0.75 2 12 60 STEADY - 17 10 min 45 23 60 10

40

36 1 2 5 60 STEADY - 6 10 min 45 7 60 2

10

10 1,5 2


5.2 MAIN AC VOLTAGE RANGE

V AC VOLTAGE OUTPUT V

LOAD CONSUMPTION

VA

LOAD TIME

min

RECOVERY TIME min

REDUCED POWER

VA 250 500 STEADY - 60 250 250 750 10 45 -

57 57 60 STEADY - 60

5.3 MAIN DC VOLTAGE RANGE

V DC VOLTAGE

OUTPUT V

LOAD CONSUMPTION

W

LOAD TIME

min

RECOVERY TIME min

REDUCED POWER

W 300 300 STEADY - 60 300 300 600 10 45 -

68 68 60 STEADY - 60

5.4 AUXILIARY AC VOLTAGE RANGE

V MAX CURRENT

mA 65 500 130 250 260 125

- Frequency range: 40 Hz to 500 Hz.

5.5 AUXILIARY DC VOLTAGE - DC voltage range: 130 V or 240 V. - DC voltage power: 90 W at full range, continuous duty, with a current limit of 0.9 A @ 130 V and 0.45 A @ 240 V.

5.6 TIMER - Maximum input: 250V a.c or 275 V DC. - Input thresholds: .With voltage Parameter Nominal value Unit Low setting 12 V DC High setting 80 V DC


. Without voltage Parameter Nominal value Unit Nominal wetting voltage 24 V Nominal wetting current 10 mA - Counting mode maximum input frequency: 10 kHz.

5.7 AUXILIARY CONTACT - Contacts range: 5 A; 250 V AC; 120 V DC

5.8 OUTPUTS MEASUREMENT

5.8.1 Current and voltage OUTPUT RANGE CHANGE

RANGE (*) RESOLUTION ACCURACY

1.999 A 1.5 A 1 mA ± (1% + 5 mA) 10 A 19.99 A 10 mA ± (1% + 20 mA) 7.999 A 6 A 4 mA ± (1% + 20 mA) 40 A

79.99 A 40 mA ± (1% + 80 mA) 19.99 A 15 A 10 mA ± (1% + 50 mA) 199.9 A 150 A 100 mA ± (1% + 200 mA)

100 A

249.9 A 100 mA ± (1% + 200 mA) 19.99 V 15 A 10 mV ± (1% + 50 mV) 199.9 V 150 A 100 mV ± (1% + 200 mV)

250 V AC

299.9 V 300 mV ± (1% + 300 mV) 19.99 V 15 A 10 mV ± (0.5% + 50 mV) 199.9 V 150 A 100 mV ± (0.5% + 200 mV)

300 V DC

299.9 V 300 mV ± (0.5% + 300 mV)

19.99 V 15 V 10 mV ± (1% + 20 mV) 65, 130 V AC 199.9 V 100 mV ± (1% + 200 mV) 19.99 V 15 V 10 mV ± (1% + 20 mV) 199.9 V 150 V 100 mV ± (1% + 200 mV)

260 V AC

299.9 V 300 mV ± (1% + 300 mV)

19.99 V 15 V 10 mV ± (0.5% + 100 mV) 130 V DC 199.9 V 100 mV ± (0.5% + 200 mV) 19.99 V 15 V 10 mV ± (0.5% + 100 mV) 199.9 V 150 V 100 mV ± (0.5% + 200 mV)

260 V DC

299.9 V 300 mV ± (0.5% + 300 mV) - NOTE: Change range is the value when the range is changed. This avoids saturation problems when we have to measure fast-changing values.


5.8.2 Other measurements N. PARAMETER , AC outputs DERIVED

FROM FORMULA UNITS

ACTIVE POWER, P Imain, Vac aux; f P= I*V*cos (f ) W 1 REACTIVE POWER, Q Imain, Vac aux; f Q= I*V*sin(f ) VAr APPARENT POWER, S Imain, Vac aux S= I*V VA 2 POWER FACTOR, p.f. f p.f. = cos(f ) -

3 IMPEDANCE, Z and f Imain, Vac aux, f Z = V/I Ohm, ° ACTIVE IMPEDANCE COMPONENT, R Imain, Vac aux; f R = Z* cos(f ) Ohm 4 REACTIVE IMPEDANCE COMP., X Imain, Vac aux; f X = Z* sin(f ) Ohm ACTIVE ENERGY, Ea I1, V2; f ; T Ea = I*V*cos

(f )*T Wha 5

REACTIVE ENERGY, Er I1, V2; f ; T Er = I*V*cos (f )*T

Whr

5.9 EXTERNAL INPUTS MEASUREMENT

5.9.1 Current measurement RANGE 20 mA RESOLUTION ACCURACY 25 mA DC 0.1 mA ± (0.5% + 0.1 mA) RANGE 10 A CHANGE RANGE RESOLUTION ACCURACY 1.999 A AC 1.5 A 1 mA ± (1% + 2 mA) 9.99 A AC 10 mA ± (1% + 20 mA) 1.999 A DC 1.5 A 1 mA ± (0.5% + 2 mA) 9.99 A DC 10 mA ± (0.5% + 20 mA)

5.9.2 Voltage measurement RANGE CHANGE RANGE RESOLUTION ACCURACY 19.999 V AC 15 V 10 mV ± (1% + 20 mV) 59.99 V AC 45 V 10 mV ± (1% + 60 mV) 199.99 V AC 150 V 100 mV ± (1% + 200 mV) 599.9 V AC 100 mV ± (1% + 600 mV) 19.999 V DC 15 V 10 mV ± (0.5% + 20 mV) 59.99 V DC 45 V 10 mV ± (0.5% + 60 mV) 199.99 V DC 150 V 100 mV ± (0.5% + 200 mV) 599.9 V DC 100 mV ± (0.5% + 600 mV)


5.9.3 Other measurements N. PARAMETER , AC INPUTS DERIVED

FROM FORMULA UNITS

ACTIVE POWER, P Iext, Vext; f P= I*V*cos (f ) W 1 REACTIVE POWER, Q Iext, Vext; f Q= I*V*sin(f ) VAr APPARENT POWER, S Iext, Vext S= I*V VA 2 POWER FACTOR, p.f. f p.f. = cos(f ) -

3 IMPEDANCE, Z and f Iext, Vext, f Z = V/I Ohm, ° ACTIVE IMPEDANCE COMP., R Iext, Vext; f R = Z* cos(f ) Ohm 4 REACTIVE IMPEDANCE COMP., X Iext, Vext; f X = Z* sin(f ) Ohm ACTIVE ENERGY, Ea I1, V2; f ; T Ea = I*V*cos (f )*T Wha 5 REACTIVE ENERGY, Er I1, V2; f ; T Er = I*V*cos (f )*T Whr

6 FREQUENCY, F Vext - Hz PASE ANGLE, IE TO V2 F , IE-V2; ref. V2 - ° 7 PASE ANGLE, VE TO V2 F , VE-V2; ref. V2 - °

PARAMETER , DC INPUTS DERIVED

FROM FORMULA UNITS

POWER, W Iext, Vext P= I*V W RESISTANCE, R Iext, Vext R = V/I Ohm

5.10 PROTECTIONS - Fuse on the mains supply. - At power-on, a diagnostic sequence controls: . Key microprocessor board components; . Auxiliary supply voltages. If something is wrong, the operator is alerted by a message. - Thermal sensor on the main and auxiliary transformers. In case of over-temperature, an alarm message is displayed. - Thermal sensors on the SCR that controls current injection, and of the internal temperature. In case of over-temperature, an alarm message is displayed. - If the following current limits and time duration of main current outputs are trespassed, the generation is interrupted, and the operator is warned by an alarm message. OUTPUT 10 A 40 A 100 A 250 Vca 300 Vcc Tmax I (A) 5 12 30 2 1 infinite I (A) 10 40 100 3 2 60 s I (A) 25 100 250 4 3 1 s - If the current of 3.5 A is exceeded on main AC or DC voltage outputs, the generation is interrupted, and the operator is warned by an alarm message.


- The auxiliary AC voltage is protected by an electronic circuit that stops the voltage generation and opens the connection to outputs socket in case of overload (short circuit included). In case of intervention, an alarm message is displayed. Via the control knob the operator can reset the alarm and close the relay to restore operation. - The auxiliary AC voltage is also protected by a thermo switch that intervenes in case of over-heating. In case of intervention, an alarm message is displayed. - The auxiliary DC voltage is protected by a current limiter. The user notices the low voltage and removes the overload. The fuse protects the case of counter-feed. - Re-triggering fuse on the auxiliary contact. - Timer inputs are protected against wrong selections. If the voltage free input is selected and a voltage is applied less than 250 V ac or 275 V DC, circuits will not be damaged. - Trip inputs and the auxiliary relay contacts are protected by devices rated 380 V AC, that limit the maximum voltage between sockets and among sockets and ground. The same protection is applied to the auxiliary AC and DC voltage sources. - The 20 mA measurement input is protected by a PTC against wrong connections: in case of error the PTC goes to high impedance. The PTC self-restores to the normal value in some minutes.


APPENDIX 1 SPARE PARTS LIST The following is the suggested list of spare parts for a duration of five years and for up to five test sets. The reference is made to the list of components. 1) N. 10 Fuses in the supply socket (1), rated T10A, code XFU22101. 2) N. 10 Fuses of the auxiliary DC voltage (19), rated F2A, code XFU23109. 3) N. 1 DC to DC converter for the display (23) backlight, code XCA10348. 4) N. 1 Encoder with switch, for MENU control knob (22), code XCM10160. 5) N. 1 Printed circuit board INTE ON-OFF (7), code PWA11400. 6) N. 1 Auxiliary DC voltage supply module (9), code YWA11395. 7) N. 1 Auxiliary AC voltage amplifier AP-50 (10), code PWA11396.


APPENDIX 2 OVERCURRENT RELAYS There are many types of time-dependent curves. They follow standards set by IEC, IEEE, IAC, ANSI, US, and are defined as Standard Inverse; Very Inverse; Extremely Inverse or so. The curve is defined by two parameters: . The setting threshold I>; . Another parameter, that can be either the Time Multiplier (K or KT), or the Time Dial setting (tI>), that is the delay with Current equal to 10 times the Pick-up Current (10I>). From these parameters the diagram can be drawn, as follows. A) Parameter KT In this instance, IEC and IEEE curves correspond to the following formula.

c

1b

II

a*K ) s (t

R

T +

−

=

Constants of the formula change according to the type of curve; they are summarised in the following table. IEC, IEEE a c b IEC Class A Standard Inverse 0.14 0 0.02 IEC Class B Very Inverse 13.5 0 1 IEC Class C Extremely Inverse 80 0 2 IEC Long Time Inverse 120 0 1 IEC Short Time Inverse 0.05 0 0.04 IEEE - US Moderately Inverse 0.0515 0.114 0.02 IEEE - US Very Inverse 19.61 0.491 2 IEEE - US Extremely Inverse 28.2 0.1217 2 IEEE - US Inverse 29.75 0.9 2 IEEE - US Short Inverse 0.0171 0.0131 0.02 With IAC and ANSI standards, the different curves correspond to the following formula.

cI

I

e

cI

I

d

cI

I

ba* K ) s (t

3

R

2

R R

T

−

+

−

+

−

+=


Constants of the formula change according to the type of curve; they are summarised in the following table.

IAC, ANSI a b c d e IAC Inverse 0.2078 0.863 0.8 -0.418 0.1947 IAC Short Time Inverse 0.0428 0.0609 0.62 -0.001 0.0221 IAC Long Time Inverse 80 0 2 2 2 IAC Very Inverse 0.09 0.7955 0.1 -1.2855 7.9586 IEC Extremely Inverse 0.004 0.6379 0.62 1.7872 0.2461 ANSI - Extremely Inverse 0.0399 0.2294 0.5 3.0094 0.7222 ANSI - Very Inverse 0.0615 0.7989 0.34 -0.284 4.0505 ANSI - Normal Inverse 0.0274 2.2614 0.3 -4.1899 9.1272 ANSI - Moderately Inverse 0.1735 0.6791 0.8 -0.08 0.1271 With US standards, the different curves correspond to the following formula.

−

+=

1c

II

ba*K ) s (t

R

T

Constants of the formula change according to the type of curve; they are summarised in the following table.

US a c b US Moderately Inverse 0.0226 0.0104 0.02 US Inverse 0.18 5.95 2 US Very Inverse 0.0963 3.88 2 US Extremely Inverse 0.0352 5.67 2


Here are the nominal inverse time characteristics for Normal, Very, Extremely and Long Time Inverse, plotted for KT from 0,1 to 1, for the case of IEC definitions.

1 10

0.1

1

1 0

100

1000

I / I>

T

K T = 0 .1

K T = 1 .0

N o rmal Inverse

1 10

0.1

1

10

100

1000

I / I>

T

KT = 0.1

KT = 1.0

Very Inverse

1 10

0.01

0.1

1

10

100

1000

I / I>

T

K T = 0.1

K T = 1.0

Extremely Invers e

1 1 0

1 0

100

1000

10000

I / I>

T

KT = 0 .1

KT = 1 .0

1

Long Time Inverse


B) Parameter t (I>) The Time Current Curves are calculated with the following equation:

( ) )(tIF

1II

A st

R

>⋅⋅

−

=

a where: ( )

1

110

AF

−

+

−= B

a

t(I>) = Set time delay at 10 times the Pick-up Current. In this instance, parameters are summarised in the following table.

Curve Type with Time Dial Setting

A

B

a

IEC Class A Standard Inverse 0.14 0 0.02 IEC Class B Very Inverse 13.5 0 1 IEC Class C Extremely Inverse 80 0 2 IEC Long Time Inverse 120 0 1 IEC Short Time Inverse 0.05 0 0.04 IEEE - US Moderately Inverse 0.0104 0.0226 0.02 IEEE - US Very Inverse 3.88 0.0963 2 IEEE - US Extremely Inverse 5.67 0.0352 2 IEEE - US Inverse 5.95 0.18 2 IEEE - US Short Inverse 0.00342 0.00262 0.02 IAC Normally Inverse 1.7868 0.03593 2.0938 IAC Short Inverse 0.05326 0.006786 1.2969 IAC Long Inverse 1.1228 0.43718 1

J819-3

ROSSO

BLU 0V

100A

0.5 QUADRI

CONNETTORE VOLANTE

NERO 0V

MARRONE

XTF20404

1 3

4

2

5

6

0.5 QUADRI L= cm

VCC

BIANCO

12 PIN

1

GIALLO 0V

ARANCIONE 0V

BLU 0V

0.25 QUADRI

F

BLU 4.5V( 11 )

BIANCO

BIANCO 0V

BLU

0

VISTA LATO FILI

TP14

INTE ON-OFF PWA11400

J804-1

J804-2J808

VIOLA

XTF10245

1

4

2

32.5 QUADRI

MODIFICA 1

NERO

0.5 QUADRI L= cm

0.5 QUADRI L=20 cm

P1

SERIALE RS232

594837261

M

BIANCO

0.25 QUADRI

( 17 )

GIALLO 11.5V

MARRONE

PICCOLO

12 PIN

( 18 )

YWA11395 VCC

J806

J818-1

J818-2

J818-3

J818-4

J800-1

J800-2

J800-3

J800-4

BIANCO 296V

BLU

J818

0.5 QUADRI

M

BLU 8V22R

0.5 QUADRI L=20 cm

ROSSO 0V

0.25 QUADRI

( 8 )

4

BLU

( 9 )

Friday, February 14, 2003

10093 3

CABLAGGIO T1000

A2

1 1

Title

Size Document Number Rev

Date: Sheet of

Designer Check and Approval

0.5 QUADRI L=20 cm

12 cm 0.5 QUADRI

CONNETTORE DI XTF20404

0.5 QUADRI

F

GIALLO 225V

0.5 QUADRI L=20 cm

BLU 0V

NERO 10V

0.25 QUADRI

( 10 )

0

NERO 0V

NERO 0V

NTC 10K

1 2

PRESA + FILTRO

T

F

N

0.5 QUADRI L=20 cm

TP13

1

12

10 GIRI

4

VERDE

BIANCO

XTF10330

1

4

2

3

VARIAC

0.5 QUADRI L=20 cm

VIOLA

TERRA

0.25 QUADRI

9 POLI

( 14 )

( 12 )

PWA11398 BP APPOGGIO

TP17

TP18

TP19

TP20

TP9

TP10

TP11

TP12

TP13

TP14

TP3

TP6

TP5

TP4

TP2

TP15

TP16

J809-1

J809-2

J809-3

J809-4

J810-1

J810-2

J810-3

J810-4

J821

J818-1

J818-2

J818-3

J818-4

J819-2

J819-3

J813-1

J813-2

J813-3

TP7TP8

J801

J802

J803

J812-1

J812-2

J812-3

J812-4

J812-5

J812-6

J816-1

J816-2

J816-3

J816-4

J816-5

J816-6

J817-1

J817-2

J815-1

J815-2

J820-1

J820-2

J811-1

J811-2

J808-1

J808-2

J819-5

J819-4

J819-1

J819-6

470R

CONNETTORE VOLANTE

0.5 QUADRI L=20 cm

( 19 )

DISPLAY

-

-

VARISTOR275V J819-3

BINCO

GIALLO 11.5V

ROSSO

VERDE

0.5 QUADRI

0.5 QUADRI L=20 cm

30 cm

5uH

0.25 QUADRI

( 1 )

( 13 )

PWA11396 AP50

J5

J2-1

J2-2

J2-3

J2-4

J4-1

J4-2

J4-3

J4-4

J4-5

J4-6

J6

J1-1

J1-2

J1-3

J1-4

J1-5

J1-6

40A

VCC

( 20 )

0.5 QUADRI L=8cmMARRONE 90V

0.5 QUADRI L=20 cm

12

CONV T1000

J805

J802

VERDE 0V

ROSA 0V

12

1

FUSIBILI230V = T5A 250V110V = T10A250V

MARRONE 38V

GRIGIO 0V

1

MARRONE 19V

BLU

SW1TERMO SWITCH

12

VIOLA 0V

1 QUADRO FASTON

VCA

100K MULTIGIRO

13

2

VAC

( 21 )

0.5 QUADRI L=8cm

BLU 0V

BLU 10V

ROSSO

ROSSO

1KSOPRA

1

MARRONE 0V

4 GIRI

12 GIRI

1R

110V

VIOLA

ROSSO

0.25 QUADRI

12 POLI

( 22 )

( 2 )

GIALLO 11.5V

100K MULTIGIRO

13

2

1234

BLU 10V

XTF10345

1

5

6

4

7

8

9

10

2

3

1112

13

14

MARRONE 38V

12

4

F

ROSSO 0V

J6

123456

PASSANTE

TP10

VERDE

1 QUADRO FASTON

110V

J4 ( AP50 )

VCC

( 23 )

( 3 )

BLU

T2XTF10245

1

5

6

4

78

910

1112

1314

15

18

19

2

3

24

2526

2728

29

3031

32

33

AC

VERDE 25V

6K8

MARRONE

1

M

TP11

BIANCO

1

1234

110V

BIANCO 11.5V

VERDE 15.2V

VERDE 15.2V

0.25 QUADRI

( 4 )

NERO

28 cm

M

J816 ( BP )

TP9

ARANCIONE 0V

ROSA 4.5V

XTF20034

GIALLO

VERDE 10V

FUSIBILE T2A

10A

1.5 QUADRI

BIANCO 0V

4.5cm

0.25 QUADRI

0.5 QUADRI

NERO 15.5V

SOPRA

( 7 )

1

( 24 )

F

2.5 QUADRI

1 QUADRO

GIALLO

GIALLO 50V

FUSIBILE RIPRISTINABILE 5A

0.5 QUADRI

14 PIN

100R

( 5 )

MEDIO

( 25 )

ROSSO 0V

ROSSO 12V

12

ROSSO

MONTATOSU AP50

TP12

1.5 QUADRI

ROSSO 7V

0.5 QUADRI L= cm

NERO 150V

16 PIN

PWA11399 BP SEGNALI

TSM-1

TSM-2

J801

J802

J803

J805

J806

19Vac-1 JP1

19Vac-2 JP1

19Vac-1 JP4

19Vac- JP4

4.5Vac-1

4.5Vac-2

17Vac-1 JP2

17Vac-2 JP117Vac-1 JP5

17Vac-2 JP5

TSA-1

TSA-2

15.2Vac

15.2Vac

0

12Vac-1

12Vac-2

10Vac-1

10Vac-2

START-1

START-2

STOP-1

STOP-2

J838

J831

J835

0.25 QUADRI

( 6 )

0

INTERRUTTORE LUMINOSO

( 15 )

ROSSO

VIOLA

NERO

XTF10330

1

5

6

4

7

89

1011

12

1314

15

1617

1819

2021

22

2

3

23

24

12 20 cm 0.5 QUADRI

GIALLO 11.5V

BIANCO

0

9 POLI L = 55

1 QUADRO

0.5 QUADRI L= cm

ENCODER

-

-

-

-

-

16 PIN

VIOLA 19V

0R5

1.5 QUADRI

AC

0.25 QUADRI

( 16 )

MICRO T1000

J801

J802

ROSSO 7V

XTF10345

1

4

2

3

GROSSO

2K2

1 QUADRO


APPENDIX 1: MENU SELECTIONS FLUX DIAGRAM

TEST CONTROL

TIMER START/STOP

AUX VAC/ VDC

METERS

RESULTS

CONFIGURATION

Aux Vac control

Aux Vdc control

Test mode Fault injection

Normal (default) Trip + pulse time Reclose mode

Maintained (default) Momentary External Timed

Start Stop

Timer

Internal (default)

External

N.O.-N.C.-EDGE Clean – 24 V – 80 V Count

Internal

External (default)

N.O.-N.C.-Edge Clean – 24 V – 80 V

OFF delay

s (default) cycles Range

Mode

Fault (default) Prefault + Fault

Prefault amplitude Prefault phase

Frequency

Locked to mains (default) Adjust freq. Value

Phase Locked to mains (default) Adjust phase Vaux-mains

Range

Internal

External V

None; P-Q; Z- f ; R- X; ; S-p.f.; Ea-Er

Amps; I/IN Volts; V/VN

AC-DC 10 A – 20 mA Waveform

AC-DC Shunt Waveform

None; P-Q; Z- f ; R-X; f V-I, f V-V; S-p.f.; Frequency; Ea-Er

Delete Settings Language Display

Selected results All results Save to address Restore address Restore default UK, FR, SP, PO, GE, IT

Speed Hold mode

Adjust phase Vaux-Imain

Output power Save

Don’t save (default) Automatic at trip Confirm at trip Manual

External I

Other internal

Auxiliary contact

Other external

Enabled Enabled

Adjust phase Vaux-Vmain

Adjust freq. R.O.C.

Slow (default) Fast Hold trip (default) Hold min Hold max

Prefault duration

Count

Prefault frequency

LCD contrast

t1000 user’s manual - user equip: new & used test equipment manual.pdf · would the test set...

Documents