T & DEnergy Automation & Information

Type KAVS

Check Synchronising Relay

IntroductionThe KAVS is a check synchronisingrelay for application to feeders ontransmission, sub-transmission anddistribution systems.

As a part of the K range or relays,the KAVS can be integrated into anoverall protection and controlsystem by utilising its integral serialcommunications facility.

Models AvailableKAVS 100

Features

• Selectable undervoltage blockingand differential voltage blockingfeatures

• Flexible operating logic optionsvia software function links

• Measurement of line and busbarvoltage, system frequency andphase angle slip frequency

• IEC 870-5 compatiblecommunications via K-Bus

• Integral event recorderaccessible from a remote PC

• Comprehensive self-checking andalarms

• Integral disturbance recorderaccessible from a remote PC

ApplicationThe KAVS checks that the voltage,phase angle and frrequency oneither side of an open circuit breakerare such that it is safe to close. Itprovides the check synchronising ordead line/bus interlocks required forsome auto-reclose applications. Italso provides split system detection,and check synchronising interlocksfor manual reconnection following asystem split.

Two voltage phase anglecomparators are included, identicalin operation, but having differentangle, slip frequency and timersettings. This allows different checksynchronising conditions to beselected for auto-reclosing andmanual circuit breaker closing. Thephase angle comparator is normallyapplied for auto-reclosing, and thesystem angle comparator for manualcircuit breaker closing.

2

Type KAVSCheck Synchronising Relay

Figure 1: Relay type KAVS

Functions

Check synchronisingThe relay checks that the two part ofthe system are in synchronism bymeasuring the angle and the slipfrequency between the line voltageand the bus voltage. Auto-reclose isblocked if these values exceed thephase angle and slip frequencysettings. Manual closure is blocked ifthese values exceed the system angleand system slip settings.

Selectable undervoltage anddifferential voltage measurements areavailable to block closure if the lineand bus voltages are not compatible.

To allow the circuit breaker to beclosed onto an uncharged line, liveline/dead bus, dead line/dead busand dead line/live bus detectors areincluded. These allow reclosure whenthe voltage on the line and/or the busVT is below a preset value.

Scheme logicThe KAVS uses ladder logic (Figure 2)to implement the scheme. It presentsthis in the form of contacts, coils,counters and timers that areimplemented in the software. Inoperation, the left side of the ladder isanalogous to a positive supply rail,with the right side being negative. Theprogram then acts as an imaginarycurrent flowing left to right, actingupon the components on the rungs ofthe ladder as appropriate. Changesto the scheme can be made through auser interface by opening or closingsoftware function links, to match thescheme to a particular application.Full details of the scheme logic usedare included in the relevant schemedescription. (See AdditionalInformation.)

Disturbance recordsThe internal disturbance recorder hasup to 2 analogue, 16 digital and 1time channel. The recorder can betriggered from selectable softwaresignals, and can store one completerecord. Data is sampled 8 times percycle and each channel can store upto 512 samples. Software isavailable to allow records to beaccessed and displayed by a PC.

Test featuresA number of features are provided toenable the relay to be thoroughlytested during commissioning, routinemaintenance and fault findingoperations:• The measurement functions allow the

analogue input and its associatedwiring to be checked.

• The on/off states of the digital inputsand relay outputs can be displayed.

Power-on diagnostics andself-monitoringPower-on diagnostic tests are carriedout by the relay when it is energised.These tests include checks on the timer,microprocessor, memory and theanalogue input circuitry. Continuousself-monitoring, in the form ofwatchdog circuitry, memory checksand analogue input module tests, isalso performed. In the event of afailure, the relay will either stopoperating, which resets the watchdogcontact, or will attempt a recovery,depending on the type of failuredetected.

Hardware Description

Inputs and outputsKAVS has 8 optically isolated inputswhich may be reassigned by the userwith any of the available functionsfrom the setting menu.

There are 8 programmable outputs,each comprising a relay with 1normally open contact which mayalso be reassigned by the user. Adedicated watchdog output with 1normaly open and 1 normally closedcontact is also available.

Typical application diagram (Figure 5)shows the input and output functionsassigned as a factory default setting.

Ancillary Functions

MeasurementThe relay can display the magnitudeof the line and bus voltages, linevoltage frequency and slip frequency.The measurements can be selected bythe user to be displayed as eitherprimary or secondary quantities.

Primary display quantities are basedon the VT ratios set in the relay. Thesequantities can provide a defaultsetting on the LCD situated on therelay frontplate.

Event recordsFifty events are stored in a non-volatilebuffer. Software is available to enablethe events to be downloaded to a PC.Any change of state of a control inpuor output relay, local setting change oroperation of a control function, isstored in the relay with a resolution of1ms. Alarms are also stored as events.

3

Figure 2: Example of ladder logic

External inputs

Break

Make

Make

Softwarerelay contactFunction link Timer Output

Softwarerelay coil

Tthe relay is housed in a Midos size4 case, suitable for either rack orpanel mounting as shown in Figure6.

A highly integrated 16-bit micro-controller uses digital signalprocessing techniques to analysepower system quantities andimplement scheme logic. The micro-controller performs all of the majorsoftware functions such as inputsignal processing, scheme logic,output relay control and handling ofthe operator interface.

The front panel contains a 2 x 16character alphanumeric back-litliquid crystal display (LCD) and 4pushbuttons to provide local accessto the relay’s menu. There are also 3light emitting diodes (LED) for visualindication of the relay’s status, ie.relay healthy, trip, alarm.

Standard Midos terminal blocks arelocated at the rear of the relayproviding connections for all inputand output circuitssuch as dc supply,ac voltage and a K-Buscommunications port.

User Interface

Front panel user interfaceThe features of the relay can beaccessed through a menu drivensystem. The menu is arranged in theform of a table, into each column ofwhich, related items (menu cells) aregrouped.

The user can move around the menuby means of the keys on thefrontplate. This can be done with thecover in place, but any change tothe settings requires the cover to beremoved.

Remote access user interfaceThe menu table can also be accessedvia the remote communications facility.This allows all of the menu cells in acolumn to be displayedsimultaneously on the screen of aPC. Changes to a menu cell can bemade from the PC keyboard.

4

Figure 3: Communications terminal arrangement

K bus screened2 core cable

Figure 4: Basic communication system

KITZ

Protocolconverter

RS232K-Bus

Relay 32 Relay 3 Relay 2 Relay 1

DesktopcomputerPC

Relay 4

Relay interconnectionThe relays are interconnected via ashielded, twisted wire pair knownas K-Bus. Up to 32 relays may beconnected in parallel across thebus.

The K-Bus is connected through aprotocol converter known as KITZ,either directly or via a modem, tothe RS232 port of the PC. The KITZprovides signals over the bus whichare RS485 based and aretransmitted at 64kbits/s. The K-Busconnection is shown in Figure 3.

This system allows up to 32 relaysto be accessed through one RS232communications port. A pictorialrepresentation of this is shown inFigure 4.

Software is available with eachKITZ to provide access to the relayto read and change settings.Additional software entitled‘Protection Access Software &Toolkit’ is available. This providesaccess to the event recorder andother additional functions.

Each relay is directly addressableover the bus to allowcommunication with any selectedrelay. Global commands may alsobe given to all relays on thenetwork.

It should be noted that protectiontripping and blocking signals arenot routed via the K-Bus. Separateconventional cabling is used for thispurpose; where appropriate theisolated 48V dc supply availableon each relay is used to energisethe optically-isolated inputs viaexternal contacts.

Communications protocolThe communications protocol usedwith K Range relays is designatedCourier. The Courier language hasbeen developed specifically for thepurpose of developing generic PCprograms that will, withoutmodification, communicate withany device using the Courierlanguage.

In the Courier system, allinformation resides within the relay.Each time communication isestablished with the relay, therequested information is loaded tothe PC. The protocol includesextensive error checking routines toensure the system remains reliableand secure.

Password protectionPassword protection is provided onsettings which alter theconfiguration of the relay, anyaccidental change to which couldseriously affect the ability of therelay to perform its intendedfunction, ie. enable/disablesettings, protection functioncharacteristic selection and schemelogic settings.

5

6

Figu

re 5

:Ty

pica

l app

licat

ion

diag

ram

KA

VS

Technical Data

RatingsInputs:

• AC voltage

• Vn (nominal)57V to 120V

• Operating range0 to 440V

• Maximum withstand375V

• Auxiliary voltage Vx24/125V or 48/250V ac or dc

• Frequency50/60Hz

• Frequency range45Hz to 65Hz

Output:

• Field voltage 48V dc (current limit: 60mA)

Burdens

• AC voltage0.02VA at 110V phase/neutral

• Auxiliary voltageThe burden on the auxiliary supplydepends upon the number of outputrelays and control inputsenergized.

No. of No. of Typicaloutput control burdenrelays inputs

DCsupply 0 0 2.5 - 6.0W

2 2 4.0 - 8.0W8 8 5.5 - 12W

ACsupply 0 0 6.0 - 12VA

2 2 6.0 - 14VA8 8 13 - 23VA

ContactsOutput relays Eight single make

• Contact ratingsMake: 30A and carry for 0.2sCarry: 5A continuousBreak: dc 50W resistive

25W inductive(L/R = 0.04s at 300V max)

Durability

• Loaded contact 10,000 operations minimum

• Unloaded contact100,000 operation minimum

Communications port (K-Bus)

• Transmission modeSynchronous

• Signal levelsRS485

• Message formatHDLC

• Data rate64 kbits/s

• ConnectionMultidrop (32 units)

• K-Bus cableScreened twisted pair

• K-Bus cable length1000m (maximum)

• K-Bus loading32 units (multi-drop system)

• ConnectorScrew terminals

• Isolation2kV rms for 1 minute

Phase angle settings

• Phase angle5° to 90°

• System angle5° to 90°

• System split90° to 175°

Slip frequency settings

• Phase angle check0.005Hz to 2.000Hz

• System angle check0.005Hz to 2.000Hz

Time settings

• Phase angle check delay0.1s to 99s

• System angle check delay0.1s to 99s

• System split time0.01s to 600s

• Auto-reclose inhibit after manualclose

0.01s to 300s

Voltage settings

• Undervoltage22V to 132V

• Differential voltage0.5V to 22V

• Line/bus dead voltage5V to line/bus line voltage

• Line/bus live voltageLine/bus dead voltage to 132V

Transformer ratios

• Voltage transformers1:1 to 9999:1

Digital inputs

Opto-isolated inputs

Eight- energized from 48V fieldvoltage

• Nominal rating 50V dc

• Off voltage≤12V

• On voltage≥35V

7

High voltage withstand

• Dielectric withstand IEC 255-5: 19772kV rms for 1 minute betweenall case terminals (exceptterminals 1) connectedtogether and the caseearth/terminals 1.2kV rms for 1 minute betweenall terminals of independentcircuits with terminals on eachindependent circuit connectedtogether.1.5kV rms for 1 minute acrossopen contacts of output relays.1kV rms for 1 minute acrossthe open contacts of thewatchdog relays.

• High voltage impulse IEC 255-5: 1977Three positive and threenegative impulses of 5kVpeak, 1.2/50µs, 0.5J between all terminalsand all terminals (exceptterminals 1) and caseearth/terminal 1.

Electrical Environment

• DC supply interruptionIEC 255-11: 197910ms interruption in theauxiliary supply.

• AC ripple on dc supplyIEC 255-11: 197912% ac ripple on the dcsupply.

• High frequency disturbance IEC 255-22-1: 1988 Class III2.5kV peak betweenindependent circuits and case.1.0kV peak across terminalsof the same circuit.No additional tolerances arerequired for the operatingtime or the unit’s thresholds.

• Fast transient disturbance IEC 255-22-4: 1992 Class III2.0kV, 5kHz applied directlyto all inputs.IEC 801-4: 1988 Level 34.0kV, 2.5kHz applied toauxiliary voltage inputs andthe watchdog relay contacts.

Atmospheric environment

• Temperature IEC 68-2-1: 1990 (cold)Storage and transit –25°C to+70°CIEC 68-2-2: 1974 (dry heat)Operating –25°C to +55°C

• Humidity IEC 68-2-3: 196956 days at 93% RH and +40°C

• Enclosure ProtectionIEC 529: 1989IP50 (dust protected)

Mechanical environment

• VibrationIEC255-21-1: 1988Response Class 1Endurance Class 1

• Shock and bumpIEC255-21-2: 1988Shock response Class 1Shock withstand Class 1Bump Class 1

• SeismicIEC255-21-3: 1993 Class 1

CaseThe relay is housed in a size 4Midos case as shown in Figure 7.

• Electrostatic discharge IEC 255-22-2: 1996 Class III8.0kV discharge in air withcover in place.Class II 4.0kV point contactdischarge with coverremoved.

No additional tolerances arerequired for the operating time orthe unit’s thresholds.

• EMC Compliance89/336/EEC

Compliance to the European Commission Directive on EMC isclaimed via the TechnicalConstruction File route. EN 50081-2: 1994EN 50082-2: 1995Generic Standards were used toestablish conformity.

• Product safety73/23/EECCompliance with European Commission Low VoltageDirective.EN 6101-1: 1993/A2: 1995EN 60950: 1992/A3: 1995Compliance is demonstrated byreference to generic safety standards.

8

97

177

Push buttonprojection 10 max.

32 21225 min.

157 max.

11103

99

52

23.54 holes Ø 4.4

168 159

Panel cut-out:Flush mounting fixing details.

All dimensions in mm.

Flush mounting.

Figure 7: Case outline size 4

9

Additional InformationKAVS 100 service manual R8506

GlossaryCourier A communications language developed to provide generic

control, monitoring, data extraction and setting changes onremote devices (primarily on protective relays) within thesubstation environment.

K-Bus The 64 kbit/s twisted pair cable used to connect Couriercompatible devices and transfer Courier data.

KITZ The interface unit which converts between K-Bus and IEC870format data.

PC Personal computer

Information required with order

Unit type

Configuration

Standard

Case size

Size 4 Midos flush mounting

Auxiliary voltage

24/125V

48/250V

Ratings

Vn = 57.7/120V

Language

English

KAVS 100

2

5

J

E

0 1

0 1 L 1

L 1

J E

Transmission & Distribution Energy Automation & Information, Le Sextant, 3 avenue André Malraux, 92300 Levallois-Perret. FranceTel: +33 (0) 1 41 49 20 00 Fax: +33 (0) 1 41 49 24 85 energy-automation.information@tde.alstom.com www.tde.alstom.com

Contact Centre on line 24 hours a day : +44 (0) 1785 25 00 70

ALSTOM, the ALSTOM logo and any alternative version thereof are trademarks and service marks of ALSTOM.MiCOM is a registered trademark of ALSTOM. Other names mentioned, registered or not, are the property of their respective companies.

Our policy is one of continuous development. Accordingly the design of our products may change at any time. Whilst every effort is made to produce up to date literature, thisbrochure should only be regarded as a guide and is intended for information purposes only. Its contents do not constitute an offer for sale or advice on the application of any product

referred to in it. We cannot be held responsible for any reliance on any decisions taken on its contents without specific advice.

Public

ation:

KAV

S/EN

BR/B

f©

200

3 A

LSTO

M

- 02

0300

- El

ectro

nic

File