megohmmeter model 1000n - userequip.comuserequip.com/files/specs/5090/1000_serv-man.pdf · the...

Rev. 8 3/04

MEGOHMMETER MODEL 1000N

(CATALOG# 185.100)

REPAIR AND CALIBRATION MANUAL

MODEL 1000N REPAIR AND CALIBRATION MANUAL CAT. #185.100

2

REV. 7: March 13, 2004 FILE LOCATION: Manuals - Cal. Man - 1000MAN.DOC

4/21/2005

TABLE OF CONTENTS

Repair and Technical Services....................................................................................... 3

Introduction..................................................................................................................... 4

Specific Features............................................................................................................ 4

Principal Characteristics ................................................................................................. 4

Specifications .................................................................................................................. 6

Operation........................................................................................................................ 7

Calibration .................................................................................................................... 11

Taking the Instrument Apart ......................................................................................... 14

Troubleshooting............................................................................................................ 17

Summary of Malfunctions ............................................................................................. 20

Component Parts List ................................................................................................... 21

Mechanical Parts List ................................................................................................... 26

Test Points ................................................................................................................... 28

Power Board Schematic and Specifications ................................................................. 29

Main Board ................................................................................................................... 30

Measure Board............................................................................................................. 31

High Voltage Board ...................................................................................................... 32

Schematics........................................................................................................... 33 & 34

Revision Description Date Approved 1 Updated Specs May 21, 1996 JPM 2 Updated Specs July 17, 1997 JPM 3 Updated Specs September 23, 1998 JPM 4 Updated Specs June 8, 1999 JPM 5 Added Power Supply Schematic and Specs August 25, 2000 JPM 6 Added changes to schematics November 13, 2000 JPM 7 Modified Board Drawings June 7, 2002 JPM 8 Z4, Z7 and Z9 changed to OP07C March 13, 2004 JPM


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REPAIR AND CALIBRATION

NOTE: Any attempts to repair and/or maintain this instrument, other than replacement of fuses and batteries, voids the warranty of the instrument. The presence of high voltages at certain locations requires servicing of this instrument by qualified personnel. It is recommended that the instrument be sent to an authorized service center.

To guarantee that your instrument complies with the factory specifications, we recommend that the unit be submitted to our factory service center at one year intervals for recalibration, or as required by other standards. For instrument repair and/or calibration, please call our factory at (800) 945-AEMC.

CHAUVIN ARNOUX®, Inc. d.b.a. AEMC® Instruments 15 Faraday Drive • Dover, NH 03820 USA (800) 945-2362 • (603) 749-6434 • Fax: (603) 742-2346

(Or contact your authorized distributor.) Estimates for repairs, normal recalibration, and calibration traceable to N.I.S.T. are available.

All customers must call for an authorization number before returning any instrument.

TECHNICAL AND SALES ASSISTANCE

If you are experiencing any technical problems, or require any assistance with the proper use or application of this instrument, please call our technical hotline:

CHAUVIN ARNOUX®, Inc. d.b.a. AEMC® Instruments (800) 343-1391 • (508) 698-2115 • Fax: (508) 698-2118 www.aemc.com


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INTRODUCTION The Model 1000N Megohmmeter is a portable instrument which is essentially intended for performing insulation tests upon various components of electrical systems and equipment. The instrument allows completion of measurements according to multiple voltage levels (step voltage method), making it possible for the user to evaluate insulation quality and to plan preventive maintenance accordingly (especially for motors).

SPECIFIC FEATURES:

• If a linear response were to be adopted for resistance and conductance, a high number of scales would be required on account of the extent of the measuring range which must be cover in practice, from 1 MΩ to 1000 GΩ. The use of logarithmic response circuitry reduces the number of scales to two. Each scale covering three decades. The accuracy is typically on the order of ± 5% over the entire range.

• Selection of the test voltages does not cause the measuring range to change. It is very easy to determine the influence of voltage upon insulation.

• An additional range is provided to cover from 1 kΩ to 1 MΩ. This range uses a constant current source (1 mA) to perform the measurement. The maximum open voltage is limited to approximately 1100 V.

• A voltmeter range covering from 0 to 600 V AC or DC allows the user to verify whether or not the circuit where the insulation must be tested is energized.

• Insulation testing and voltmeter functions are accompanied by a continuity test range from 0.1Ω to 100Ω. The logarithmic scale provides excellent accuracy between 0.1Ω to 1Ω. A fuse is used for overload protection in case of incorrect measuring procedures.

PRINCIPAL FEATURES: Insulation Testing: • Test voltages - The rotary selector switch allows the choice of five voltages:

50 V, 100 V, 250 V, 500 V, 1000 V. • Ranges for each test voltage

MΩ: 1 MΩ to 1000 MΩ (typical accuracy: ± 5% of reading, max: ± 10% of reading) GΩ: 1 GΩ to 1000 GΩ (typical accuracy: ± 5% of reading, max: ± 10% of reading) KΩ: 1 KΩ to 1000 KΩ (typical accuracy: ± 5% of reading, max: ± 10% of reading) NOTE: From 100 GΩ to 1000 GΩ, the typical accuracy is ± 10% and max. is ± 20% of

reading on the 50 V range.


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Continuity Testing:

0.1Ω to 100Ω (typical accuracy: ± 5% of reading, max: ± 10% of reading or 5 mΩ) The logarithmic scale is the same for the Ω and KΩ range. The 0.1Ω is calibrated at the output terminal of the instrument. You need to subtract the resistance value of the leads from your measurement if you need the accuracy under 10Ωs.

DC or AC Voltage Measurements:

In order to ensure that the system under test is not energized, the instrument functions as a voltmeter as soon as it is connected, provided the push-to-measure button has not yet been pressed. This is the case for every range selected.

Scale: 0 to 600V AC or DC: accuracy: 3% of full scale

Time Constant:

K M G

Charging time (R reading) x (C reading) 0.04 Sec / µF 4 Sec / µF

Discharging time 0.1 Sec / µF or 0.3 Sec / µF to decrease below 50 V

Safety Features: • This instrument is capable of withstanding overloads of up to 600 V for any selected function. • The continuity range is protected by a fuse inserted in the "G" (Guard) terminal and is

accessible when the battery compartment is removed. Influence: • Temperature: Twice the accuracy per 10° C variation

Supply voltage: Half the accuracy for battery voltages between 9 and 13 Volts • Humidity: No significant influence up to 40° C and up to 70% relative humidity Dielectric Strength: • 4000V RMS at 50 Hz for 1 minute between all input terminals and any accessible metal

portions of the instrument. • Model with AC power supply accessory: Add test at 4000V RMS at 60 Hz for 1 minute

between the AC outlet and any accessible metal portions of the instrument.


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SPECIFICATIONS: ELECTRICAL INSULATION TESTS DC TEST VOLTAGE: 50, 100, 250, 500, 1000 V

MEGOHM RANGE: For each test voltage two direct reading ranges 1 to 1000 MΩ 1 to 1000 GΩ (1,000,000 MΩ)

SHORT CIRCUIT CURRENT: 5 mA (max)

ACCURACY: 5% of reading typical 15 % of reading between 100 MΩ to 1000 GΩ on the 50V range

CHARGING TIME: 1000 MΩ range: 0.3 s/µF 1000 GΩ range: 4 s/µF

DISCHARGE TIME: Automatic discharge when test button is released; 0.1 s/µF

SCALE: Two large overlapping scales: 4.7" (119 mm) for each range

TEST VOLTAGE GENERATION: Solid state circuitry generating rated test voltage across the full range RESISTANCE TESTS TEST CIRCUIT: Constant 1 mA DC

KILOHM RANGE: 1 to 1000 kΩ

MAXIMUM TEST VOLTAGE: 1200 V DC

ACCURACY: 5% ± 100Ω of reading typical CONTINUITY TESTS TEST CURRENT: Constant 10 mA DC

OHM RANGE: 0.1 to 100Ω (3Ω midscale)

ACCURACY: 5% ± 0.05 Ω of reading typical

FUSE PROTECTION: 0.3 A high interrupting capacity fuse

VOLTAGE TESTS (SAFETY CHECK) VOLTAGE RANGE: 0 to 600 V DC

ACCURACY: 3% of full scale GENERAL SPECIFICATIONS AUDIBLE TEST SIGNAL: Ten beeps per minute for insulation and resistance tests; continuous tone for continuity test reading ≤ 200Ω

POWER SUPPLY: Eight 1.5 V "AA" alkaline batteries (NEDA 15A). Typical battery life: 350 one-minute tests; power consumed only when test button is depressed; built-in battery check by green LED. OPTION: 110/220 V selectable, 47 to 400 Hz AC supply module

DIELETRIC TEST: 4000 V AC, 60 Hz, 1 min

METER MOVEMENT: Rugged taut band suspension

DIMENSIONS: 7.7 X 5.2 X 3.75" (196 X 132 X 95 mm)

WEIGHT: 2.2 lbs (1 kg)

TEMPERATURE RANGE: 23 to 122°F (-5 to 50°C)

CASE: High impact gray polycarbonate

TERMINALS: Color-coded safety terminals; guard terminals eliminates surface leakage errors

SAFETY/REFERENCE STANDARDS


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OPERATION: a) Mode of Operation for MΩ and GΩ:

An oscillator (Z1) provides a low voltage signal which is amplified by the transformer (T1) then rectified and filtered (CR201, C201). This high DC voltage is regulated through the divider (R202 to R209) and the operational amplifier (Z4). When the range switch is turned to select a new voltage range, the input of (Z4) is open. In order to prevent an increase in the high voltage, two diodes (CR12 and CR13) are connected to the + supply in order to always bring the output of Z4 to the + supply and stop the oscillation of Z5 and the high voltage.

HV GENERATOR

LOGARITHMIC

AMPLIFIER

G

RX

Vd

VmCR

VHT

+ -

RM

DIVIDER BRIDGE MEASURING SHUNT

RX = ( )VHT

VM1 RM, or VM

VHT ∗ RM

RX=~

VM = K

RX

Because RM is significantly lower than RX, the portion of the curve which is used, VM =f (RX ) ,

can be expressed as a function KRX

.

Measurement for the MΩ range with test voltages of 50 and 100 Volts is performed by measuring the voltage drop on the shunts R101 and R102. For test voltages of 250, 500, 1000 Volts is performed through the current shunt R102 only. Measurement for the GΩ range is performed by measuring the voltage drop on the shunt R103. The resulting voltage is then filtered and passed through a variable gain amplifier (Z5) then into a logarithmic amplifier (Z4). Temperature compensation is provided to the amplifier by a thermistor (TH1). The last amplifier (Z7) provides the current needed to drive the meter movement G1. A negative 4.6 Volt supply is provided by (Z3) for powering the quad amplifier (Z2).


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The beeper (BZ1) is power by the oscillator (Z8) and the transistor (Q3) every six seconds, except for when in the ohm range where the comparator (Z2) allows the beeper to operate continuously for resistance levels under 200Ω. The comparator (Z2) permits the "BAT" led to turn off whenever the battery voltage is less than 9 V DC. The resistors (R214) and (R215) allow the circuit under test to discharge when the push-to-measure button is released. The protection of the measuring circuit in case of a short circuit between the positive and negative terminals is provided by the discharger (E101) for voltages exceeding 90 V.

b) Mode of Operation for KΩ

HV GENERATOR LOGARITHMIC

AMPLIFIER

G

RX

Vd Vm

VHT

+ -

CONTROL SHUNT

KR

RR104

CR

During the operation of the circuit loop, VD = cte. Therefore, a constant current flows through (R104) and (RX). VHT varies in proportion to RX, and a resistance bridge permits bleeding of a portion of VHT in order to perform the measurement.

VM =RXK

I +R104

K

I =CONSTANT

The voltage output is limited to approximately 1300 Volts when the measuring terminals are open.


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c) Voltmeter - Mode of Operation:

When the push-to-measure button is up, the Model 1000 Megohmmeter functions as a DC or an AC voltmeter. The input resistance is close to R214 + R215 = 90 KΩ. The voltage is reduced by means of (R212) and (R213) and rectified by the diode (CR10) and (CR11).

R214

47 K

R215

47 K

R212

2.67 MR213

291 K

C202

1 uF

R50 R51

G

CR10

+

-

--Positive voltage

--Positive alternation

R214

47 K

R215

47 K

R212

2.67 MR213

291 K

C202

1 uF

R50R51

G

CR11

+

-

--Negative voltage

--Negative alternation


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d) Ohmmeter - Mode of Operation:

CONSTANT

CURRENT

GENERATOR

(RX)

(G)

Shift from 0 to 0.1 Ohm

for Start of Scale

Measuring Amplifier

(Z5)

(R26)

The high voltage section is not used when the instrument functions as a ohmmeter. (Q2) and (CR3) constitute a constant current generator. The current generated flows through the resistor under test (RX). The respective voltage (VRX) is directly measured by the amplifier (Z5).


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CALIBRATION: Recommended Cleaning Procedures:

The exterior should be cleaned periodically with a cloth moistened with water and a mild detergent solution. (Do not use chlorinated solvents or solvents containing hydrocarbons). Wipe the instrument and let it dry completely before using it again.

NOTE: The adjustment procedures described below should be performed under the following

environmental conditions: Temperature: 21°C ± 3°C Humidity: 30 to 60% RH

Required Items:

• 1 DC power source, with adjustable voltage between 8 to 15 V (1 A Max.) • 1 DC ammeter (minimum range: 0.5 A), with voltage drop less than 0.1 V. • 1 Voltmeter with 20,000 cts of resolution capable of measuring at least 10 V.

Impedance ≥ 1 MΩ • 1 Set of resistors 1 MΩ, 100 MΩ, 1000 MΩ, 100 GΩ, 1000 GΩ (accuracy 1% or less,

operating voltage > 1000 V). • 1 Resistor 100 Ω / 1% • 1 Resistor 0.1 Ω / 1% • 1 AC power source, 0 to 600 V 50/60 Hz ± 1%

Calibration Procedures:

a) With the push-to-measure button disengaged, provide 600 V AC between the + terminal (green) and the - coaxial plug. The reading must be between 582 and 618 V (± 3% fs). Otherwise consult the troubleshooting section.

b) Remove the bottom portion of the instrument by unscrewing the two center screws when the push-to-measure button is up, (See section B on page 13). This allows access to the adjustment potentiometers.

IMPORTANT: This is a high precision instrument. It is very important to keep the printed circuit

boards absolutely clean. Do not touch the circuit boards with fingers and prevent foreign substances from coming into contact with the boards.

c) Initial Conditions: Place the potentiometer A1 to the farthest counter-clockwise position.


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d) Offset adjustment of the amplifier (Z5) when RX = ∞ (open) • Supply the Model 1000 with 10.5 V DC. • Connect the voltmeter between the T and D solder pins (the ground connection D can be

made on the spacer of the high voltage switch.) • Select the 250 V / MΩ range and push down the on/off switch. The beeper must "beep"

approximately every 6 seconds. • Adjust the potentiometer A101 to obtain a reading of 0 ± 40 µV on the voltmeter. • Select the 50 V / GΩ range and verify the reading is still 0 ± 200 µV. • Select the 1000 V / GΩ and adjust the potentiometer A103 to read 0 ± 200 µV on the

voltmeter.

NOTE: Because the two settings are highly sensitive, it is necessary to allow a few seconds between adjustments in order to obtain a stable reading, especially for the GΩ range. Never short circuit the terminals at this stage, a memory effect on the input capacitor may produce an incorrect zero.

e) Adjusting the "1" point on the MΩ scale:

• Select the 500 V / MΩ range and measure 1 MΩ. • Adjust the potentiometer A4 to read "1" on the MΩ scale.

f) Adjusting the "100" point on the MΩ scale:


g) Adjusting the "1000" point on the MΩ scale:


NOTE: The adjustment of the potentiometer A5 and A102 are interdependent. It is necessary to

perform these two tests until the two readings are perfect.

h) Adjusting the Ohmmeter: • Select the 10 mA range on the instrument. • Measure 100Ω and adjust the potentiometer A2 to read "100" on the ohms scale. • Measure 0.1Ω and adjust A3 to read "0.1" on the ohms scale. • During this adjustment check the reading on the voltmeter connected between the point T

and D. The value must be positive ( ≅ + 8 mV ). Otherwise, it is necessary to continue adjusting A3.

• It is necessary to verify the linearity at several locations. • The deviation should be less than or equal to 1 mV from the theoretical value (or 5%). • For resistor values under 200Ω the beeper must be "on" continuously.


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NOTE: The 0.1Ω resistor must include the value of the leads used in the calibration.

i) Adjustment of the Short Circuit Current: • Connect an ammeter in series with the battery supply and adjust battery voltage to

9 V DC. • Select the 1000 V / MΩ range. • Measure RX = 1 MΩ and note the power consumption on the ammeter. • Measure RX = 0 and adjust A1 to obtain the prior current ± 20%. • The green LED should turn off when the battery voltage drops below 9 V.

j) Select the 1000 V / GΩ range and measure RX = 1 MΩ, 10 MΩ, then 100 MΩ. The needle must always deflect to the left side. If not, add the diodes CR14 and CR15 to the main board. (If not already modified).

NOTE: Let the instrument set for at least one hour before testing the specification on all the

ranges. The short circuit on step “j” disturbs the offset of the amplifier especially on the 50 V / GΩ range.


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TAKING THE INSTRUMENT APART: Necessary Tools:

• Standard screwdriver • 30 W soldering iron • Desoldering iron • Phillips No 2 screwdriver

IMPORTANT: This is a high precision instrument. It is very important to keep the printed circuit boards absolutely clean. Do not touch the circuit boards with fingers and prevent foreign substances from coming into contact with the boards.

A) Opening the Battery Compartment: • Be sure the push-to-measure button is up (instrument off). • Place the instrument on the table with the front panel down and loosen the four embedded

screws holding the battery compartment closed. Pick up the instrument with one hand and turn it over while covering the open battery compartment with the other hand. This allows the battery pack to be removed easily. Then place the instrument back on the table with the front panel down while holding the exposed battery pack. Be careful not to damage the battery connector when disconnecting it.

B) Removing the Bottom Case: • Be sure the push-to-measure button is up (instrument off). • Place the instrument on the table with the front panel down. • Use a screwdriver to loosen the two center screws which secure the bottom panel. • Lift up the bottom panel and turn it upside down in order to let the two screws drop out. • Set the bottom down and disconnect the battery connector. • During reassembly, the same procedure should be done in reverse order.

C) Removing the Printed Circuit Board Assembly: • The push-to-measure button must be engaged in order to lock the spring and ball mounted

within the cap. • Set the instrument upon the table with the front panel facing downward (after removal of the

front panel). Use a Philips screwdriver to loosen the three fastening screws holding the bottom board to the front panel.

• With a standard screwdriver, unscrew the large center screw beneath the printed circuit assembly. Remove all the screws and desolder the wire from the green terminal. The board assembly can now be lifted slightly to allow the desoldering of the shielded cable, its ground connection, and the red wire from the blue terminal.

• In order to remove the set of printed boards from the case, pull the high voltage transformer forward and tilt the boards over the table before unsoldering the two galvanometer wires.


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D) Removing the Selector Switch Rod: • Place the top panel on the table in an upside down position. • Remove the attachment clamp and then remove the metal washer and spring washer. Lift

up the panel in order to remove the selector switch rod. • The same procedure should be completed in reverse during reassembly.

E) Removing the Galvanometer: • With the case turned forward, use a Philips screwdriver to remove the two screws which

secure the galvanometer. Use two fingers to gently push aside the two splines that hold the dial in place. Lift the galvanometer with other hand and remove it.

• The same procedure should be completed in reverse during reassembly. WARNING: The inner portion of the transparent surface is covered by an antistatic solution. Avoid

rubbing or cleaning this part if you do not have a replacement for this solution.

F) Removing the Bottom Board (disassembling): • The push-to-measure button must be locked into a lower position. • With the bottom resting upon the table, unsolder the four wires coming from the high voltage

switch, then the two wires from the transformer (red and black). Remove the screw fastening the high voltage switch (located on the high voltage board).

• Turn the instrument over and removed the seven screws which secure the bottom board. • As you pull the high voltage push button outward, turn the bottom board in relation to the

supporting layer. • At this point all of the components on the bottom board are accessible.

G) Removing the High Voltage Board: • The high voltage button must be locked into a lower position. • The bottom board must face downward, toward the table. • Unsolder the three connecting wires between the high voltage board and the high voltage

switch. Then the two wires from the transformer (red and black). • Remove the six fastening screws (three of these screws are secured by a flat washer and a

lock washer). • Turn the high voltage board in relation to the supporting layer.

H) Removing the Measurement Board: • Remove the bottom and then the high voltage board as described above.


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I) Reassembling the Printed Circuit Boards: • In order to reassemble the printed boards, complete the previously described procedures in

reverse, but do not tighten the screws completely. Slide the rod into the selector switch opening to ensure proper alignment of the boards. The rod must be able to turn freely without being obstructed. Then you can tighten all the screws.

J) Removing the High Voltage Switch: • The high voltage button must be locked into a lower position. • Position the bottom board so that the circuits face upward. • Use the desoldering iron to undo the eight solder points between the high voltage switch and

the bottom board. • Turn the bottom board over and perform the same procedures described in Section H. • During reassembly, the same procedure should be done in reverse order.

K) Reinstalling the Printed Circuit Assembly: • The push-to-test button should be engaged. • With the panel turned forward, place the printed circuit boards beside it. The bottom board

should face up. • Be sure the LED is perpendicular to the printed circuit boards. • Resolder the two galvanometers. The red wire should be connected to the positive terminal

and the green wire to the negative terminal. • Place the printed circuit board assembly into the panel without pushing it in entirely. • Resolder the wire for the negative terminal (white) to the bottom board, along with the

respective ground wire (yellow). Then resolder the guard terminal wire (red). • Fully secure the bottom board with the three Philips screws and the center screw. • Resolder the last wire (white Teflon) to the positive terminal (green).


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TROUBLESHOOTING: Check the condition of the batteries before performing any troubleshooting procedures. The green "BAT" light turns of whenever battery condition is lower than approx. 9 Volts (See Section A on page 13). While taking the instrument apart, consult the wiring diagrams and board layouts. These diagrams indicate various testing points for the unit. Necessary Items for Troubleshooting:

• Standard screwdriver • 30 W soldering iron • Philips screwdriver • 15 V DC power supply (1 Amp) • 5 V DC power supply (100 mA) • 50 V/Div. oscilloscope • Voltmeter with 10 µV resolution and a minimum input resistance of 1 MΩ • 1 MΩ resistor (voltage > 1000 V)

IMPORTANT: Because the circuits must be kept absolutely clean in order to insure the accuracy

of the instrument, careful handling is essential. The high voltage switch, the high voltage board, and the measuring circuit should be manipulated by means of the transformer or the printed circuit assembly.

Indications of Improper Functioning:

(1) The instrument does not function at all (no movement of the pointer; the battery light is not lit; the beeper does not operate):

• Set the selector switch at 50 MΩ, with the push-to-measure button in a raised position. • Open the battery compartment in the manner described in section A on page 13. • Disconnect the battery connector. • Test the eight 1.5 V alkaline "AA" batteries. • If the voltage is less than 10 V, replace the batteries. Be sure to maintain the proper polarities. • If the voltage is higher than 10 V, reconnect the battery connector. • Measure the voltage level at the terminals for (C102). These terminals are accessible from

the battery opening. If there is no voltage, the battery connector is not connected. If the voltage decreases sharply, (C102) is defective. • If the proper voltage is present in the above measurement, press the push-to-measure button.

If the voltage drops sharply, a component within the bottom board is consuming excessive power. This will require the disassembly of the bottom circuit board. (See Section C on page 13).

• Unsolder the wires extending from the primary on the high voltage transformer.


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• Supply voltage to the circuits with a voltage level of 12 V while monitoring the current with an ammeter connected in series. Normal consumption is typically less than 50 mA.

• Excessive power consumption may be attributed to a short circuit at (Q1), or to defects in the integrated circuits identified as (Z1), (Z4), and (Z8). Because these circuits are situated upon mountings, they should be disconnected one by one until proper power consumption is obtained.

• If none of the previously cited circuits is defective, it is advisable to check the capacitors identified as (C24) and (C25) for probable leakage or short-circuiting.

• When the proper power consumption has been obtained, check the + 5 V and the - 5 V levels, as well as the voltage level of diode (CR1) (+ 2.5 V).

• Disconnect the power source and reconnect the primary of the transformer.

2) Checking the Zero Setting for 1000 V / GΩ: • Reassemble the three printed circuit boards. Then fit the rod into the switch and select 250

V / MΩ. • Supply 10.5 Volts to the instrument. Place the voltmeter between point T and point D, and

perform the calibration procedure contained in Section d on page 11. • If the voltage at point T exceeds 0 ± 200 µV when the selector is in the 1000 MΩ position, it

will be necessary to clean all of the printed circuit boards. • Disconnect the instrument and remove the small white push button for the high voltage

switch, the push button cap, and the respective ball bearing and spring. These components should not be placed in the cleaning solution while the circuits are soaking. After drying, reinstall these items within the panel and perform all of the indicated calibration procedures. (Consult Section b on page 10)

3) The battery light is lit and the beeper operates properly but measurement is

not possible: Select the 250 V / MΩ range and connect a voltmeter set to the 1000 Volt range to the measuring terminals. (a) No voltmeter movement (control component not functioning).

• The circuit boards will have to be removed. • Place the circuit boards upon the respective supporting layer (transformer facing up) and fit

the rod into the switch. Then select the 250 V / MΩ range. • Supply 12 Volts to the circuit and verify the supply and reference voltage levels.

It is possible to check the open loop control sequence by adopting the following precautions. • Open the loop at the point identified as (h) on the high voltage board. Position the high

voltage board switch between the 50 V and 100 V plugs. A finite gain should be established for the control loop by placing a resistor which can provide a sufficient number of KΩ between the lugs identified as (2) and (3) within (Z1).

• The control loop should be placed in operation by supplying a voltage level of + 5 V (to start from zero) to approximately + 2.5 V at point (h). This voltage level corresponds to the theoretical control point.


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• Check the test points identified as (4), (5), (6), and (8). • Proper functioning at point (6): Check (T1), (CR201), and (C201). • Proper functioning at point (5), but not at point (6): Check (Q1) and (CR2). • No oscillation at point (5): Check the voltage level at the lug identified as (1) on (Z1). • Voltage ≈ 2.5 V: (Z1) is defective. • Voltage level not equal to 2.5 V: Check (Z4) or (CR5) and replace defective component.

Proceed in accordance to the description of removal of printed circuit boards on pg. 13. • Replace the circuit boards and proceed with verification of zero setting for 1000V / MΩ. • Remove the bottom circuit board in order to gain access to the components. • After reassembling the circuit board, complete the procedures in Section d on pg 11.

(b) The voltmeter reading is 250V (high voltage available, but measuring circuit is not functioning): • Check the fuse (F101, 0.315 A) that is accessible after removing the battery

compartment cover. (See Section A, on page 13). • If the fuse is defective, it must be replaced. • If the fuse is not defective, it is necessary to remove the bottom panel. • Connect the voltmeter between the locations identified as T and D (an identical

grounding location can be selected on the binding posts for the high voltage switch), and set the voltmeter at 250 V / MΩ. When the button is engaged, the voltmeter reading should be approximately 4 V when resistance of 1 MΩ is being measured.

• Voltage level not appropriate: check (Z5) or (C103). • Appropriate voltage level: Remove printed circuit boards (Section C, page 13) and use an

ohmmeter to determine if the circuit boards are disconnected. If disconnected, reconnect the boards.

• Place the circuit board assembly upon the supporting layer and move the switch to 250 V / MΩ. Then it is necessary to connect a 1 MΩ resistor to the measuring output wires by soldering. Supply power to the boards with a voltage level of 12 V. The voltage at point T should be approximately 4 V. The output voltage for (Z6) (test point 11) should be approximately 50.7 mV. Otherwise, (Z6) is defective. The output voltage for (Z7) (test point 12) should be close to zero. Otherwise (Z7) is defective.


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Summary of Malfunctions:

• Control functions begin at over voltage level between two steps on the selector switch: Leakage from (CR5), (Z4), and (CR6), towards (Z1).

• Adjustment of the short-circuit current: Transformer (T1) - (Z1) not operable. • Impossible to obtain "0" on the MΩ and GΩ scales: The connecting layer has been cut at

(A101), (A103), or (Z5). • Incorrect zero position for 1000 V / GΩ: The circuits are not clean, or there is insufficient

protection for selector rod circuits. No contact with small protective strip: (C103) is defective. • Incorrect KΩ readings: (Z2). • Incorrect voltage readings: (R212). Unsuitable power consumption levels for printed circuit

assembly (I = 100 A for 600 V point). • Defective functioning of beeper: (Z8), (Q3), beeper. • Battery light does not function: (Z2c), (CR9). See Back of Manual for Schematics


21


4/21/2005

IX. PARTS LIST:

MAIN BOARD #679473-93

R1 3.3 K 5 % 1/4 W STANDARD 522152M00 R2 18 K 5 % 1/4 W STANDARD 521779D00 R3 1.5 K 5 % 1/4 W STANDARD 521823L00 R4 100 K 5 % 1/4 W STANDARD 521779C00 R5 18 K 5 % 1/4 W STANDARD 521779D00 R6 1 K 5 % 1/4 W STANDARD 521779H00 R7 22 K 5 % 1/4 W STANDARD 521779B00 R8 150 5 % 1/2 W CARBON 521586C00 R9 10 K 0.5% 1/8 W 50 ppm 523454E00 R10 15 K 0.5 % 1/8 W 50 ppm 524404N00 R11 24.9 K 1 % 1/8 W 50 ppm 524222Z00 R12 249 K 1 % 1/8 W 50 ppm 524068A00 R13 240 K 5 % 1/4 W STANDARD 524024A00 R14 7.5 M 5 % 1/2 W CARBON 521917Q00 R15 470 K 5 % 1/4 W STANDARD 522635F00 R16 10 M 5 % 1/4 W COMPACT 523989C00 R17 100 K 5 % 1/4 W STANDARD 521779C00 R18 150 K 1 % 1/8 W 50 ppm 523886V00 R19 100 K 1 % 1/8 W 50 ppm 523803G00 R20 100 K 5 % 1/4 W STANDARD 521779C00 R21 22 K 5 % 1/4 W STANDARD 521779B00 R22 10 5 % 1/4 W STANDARD 552152R00 R23 169 1 % 1/4 W 50 ppm 523014W00 R24 470 5 % 1/4 W STANDARD 521779G00 R25 4.7 K 5 % 1/4 W STANDARD 521779A00 R26 0.08 5 % WOUND 68 B 524542A00 R27 1 K 5 % 1/4 W STANDARD 521779H00 R28 40.2 K 1 % 1/8 W 50 ppm 523803C00 R29 100 K 5 % 1/4 W STANDARD 521779C00 R30 1 M 5 % 1/4 W STANDARD 521823Z00 R31 49.9 K 1 % 1/8 W 50 ppm 523803E00 R32 22 K 5 % 1/4 W STANDARD 521779B00 R33 1 K 5 % 1/4 W STANDARD 521779H00 R34 47 5 % 1/4 W STANDARD 522152T00 R35 47 5 % 1/4 W STANDARD 522152T00 R36 499 K 1 % 1/4 W 50 ppm 523433P00 R37 499 K 1 % 1/4 W 50 ppm 523433P00 R38 1 M 1 % 1/4 W 50 ppm 522711Y00 R39 4.02 M 1 % 1/4 W 50 ppm 523433Q00 R40 100 K 1 % 1/8 W 50 ppm 523803G00 R41 178 K 1 % 1/8 W 50 ppm 523886X00 R42 178 K 1 % 1/8 W 50 ppm 523886X00

R43 1 K 1 % 1/8 W 50 ppm 523087T00 R44 1 K 1 % 1/8 W 50 ppm 523087T00 R45 3.01 K 1 % 1/8 W 50 ppm 523014M00 R46 4.99 K 1 % 1/8 W 50 ppm 523921N00 R47 10 K 1 % 1/8 W 50 ppm 523087G00


22


4/21/2005

R43 TO R47 RESISTOR NETWORK 682636-79 R48 499 1 % 1/8 W 50 ppm 523921L00 R49 8.87 K 1 % 1/8 W 50 ppm 523128G00 R50 10 K 1 % 1/8 W 50 ppm 523087G00 R51 10 K 1 % 1/8 W 50 ppm 523087G00 R52 4.42 K 1 % 1/8 W 50 ppm 523128L00 R53 22 K 5 % 1/4 W STANDARD 521779B00 R54 100 K 5 % 1/4 W STANDARD 521779C00 R55 2.2 K 5 % 1/4 W STANDARD 521823J00 R56 10.2 1 % 1/8 W 50 ppm 523128V00 R57 59 K 1 % 1/8 W 50 ppm 523886U00 R58 2.37 K 1 % 1/8 W 50 ppm 524068E00 R59 1 K 5 % 1/4 W STANDARD 521779H00 R60 100 K 5 % 1/4 W STANDARD 521779C00

A 1 2.2 K 20 % SINGLE TURN CERMET VA 05 V 522956C00 A 2 47 20 % SINGLE TURN CERMET VA 05 V 522956P00 A 3 10 K 20 % SINGLE TURN CERMET VA 05 V 522956G00 A 4 200 K 10 % MULTITURNS CERMET 523108L00 A 5 2.2 K 20 % SINGLE TURN CERMET VA 05V 522956C00

CR 1 DIODE LM 336 Z ZENER 2.49 V 522754Z00 CR 2 DIODE 1N 4002 99-DOD 100017 CR 3 DIODE LM 336 Z ZENER 2.49 V 522754Z00 CR 4 DIODE 1N 4002 99-DOD 100017 CR 5 DIODE 1N 4148 99-DOD 100018 CR 6 DIODE BZX 55C10 ZENER 10 V 521954E00 CR 7 DIODE BZV 48C15 ZENER 15 V. 5 W 524332E00 CR 8 DIODE 1N 4148 99-DOD 100018 CR 9 DIODE GREEN LED 10 mA / 2 mcd 523175P00 CR 10 DIODE 1N 4148 99-DOD 100018 CR 11 DIODE 1N 4148 99-DOD 100018 CR 12 DIODE BAT 42 SCHOTTKY 524111C17 CR 13 DIODE 1N 4148 99-DOD 100018 CR 14 DIODE 5 PAD 50 (Added between traces) 523300V00 CR 15 DIODE 5 PAD 50 (Added between traces) 523300V00 Th1 THERMISTOR TSP 102 <CTP 1000 Ω 5 % = 0.7 % °C 523659C00

C1 CAPACITOR 1 F 50 V ELECTROLITIC ALU. 524401F20 C2 CAPACITOR 1 F 100 V 10 % POLY. 524121U00 C3 CAPACITOR 0.1 F 100 V 10 % POLY. 524121B20 C4 CAPACITOR 0.1 F 100 V 10 % POLY. 524121B20 C5 CAPACITOR 10 F 35 V ELECTROLITIC ALU. 524401B20 C6 CAPACITOR 10 F 35 V ELECTROLITIC ALU. 524401B20 C7 CAPACITOR 10 F 35 V ELECTROLITIC ALU. 524401B20 C8 CAPACITOR 1 F 100 V 10 % PLASTIC 524121U00 C9 CAPACITOR 100 pF 500 V 10% CERAMIC 520739N27 C10 CAPACITOR 10 F 35 V ELECTROLITIC ALU. 524401B20 C11 CAPACITOR NOT USED C12 CAPACITOR 0.22 F 160 V 10 % POLYPROPYLENE 524377A00 C13 CAPACITOR 22 nF 160 V 10 % POLYPROPYLENE 524276A00 C14 CAPACITOR 10 F 35 V ELECTROLITIC ALU. 524401B20 C15 CAPACITOR 4.7 nF 400 V 10 % POLY. 524121H20


23


4/21/2005

C16 CAPACITOR 0.1 F 100 V 10 % POLY. 524121B20 C17 CAPACITOR 0.1 F 100 V 10 % POLY. 524121B20 C18 CAPACITOR 1 F 50 V ELECTROLITIC ALU. 524401F20 C19 CAPACITOR 0.1 F 100 V 10 % POLY. 524121B20 C20 CAPACITOR 100 pF 500 V 10% CERAMIC 520739N20

Q 1 TRANS. TIP 31 C NPN (100V-3A) 523675S00 Q 2 TRANS. BD 520 PNP (80V-0.5A) 523739B00 Q 3 TRANS. BC 307B PNP 523015W20 Q 4 TRANS. BC 184C NPN 523206Q20 Z 1 IC. TL 495CN (Power supply control circuit) 524001F14 Z 2 IC. TL084CN (Quad. bi-FET) 524001M00 Z 3 IC. ICL7660 CPA (Voltage converter) 524165C17 *Z 4 IC. MLM 308 API 523584T17 Z 7 IC. OP07C 903.MXL 100051 Z 5 IC. ICL 7650 CPD (Chopper-amplifier) 524156G14 Z 6 IC. AD 536 AJH (RMS converter) 524280-00 *Z 7 IC. MLM 308 API 523584T17 Z 7 IC. OP07C 903.MXL 100051 Z 8 IC. ICM 7555 IPA (Timer) 523093Q00

G1 METER MOVEMENT I= 100 A FOR 97 °DEFLECTION 679433-90 T1 H.V. TRANSFORMER 3000/100 TURNS 679293-93 BZ 1 3000 HZ BEEPER (3V TO 15 V, 20 mA) 524338A00

* NOTE: Z4 and Z7 were replaced by OP07C (903.MXL 100051) Remove C9 and C20

MEASUREMENT BOARD ASSEMBLY #679298-95

R101 36.2 K 0.25 % 1/8 W 25 ppm 524996G00 R102 3.92 K 0.25 % 1/8 W 25 ppm 524986F00 R103 a 1 M 0.1 % 1/8 W 25 ppm 524986H00 R103 b 1 M 0.1 % 1/8 W 25 ppm 524986H00 R103 c 1 M 0.1 % 1/8 W 25 ppm 524986H00 R103 d 1 M 0.1 % 1/8 W 25 ppm 524986H00 R103 e 20 K 1 % 1/8 W 50 ppm 523802J00 R104 2.4 K 0.25 % 1/8 W 25 ppm 524986E00 R105 1 M 1 % 1/8 W 50 ppm 523941J00 R106 1 M 1 % 1/8 W 50 ppm 523941J00 R107 100 1 % 1/8 W 50 ppm 523839R00 R108 402 1 % 1/8 W 50 ppm 523921W00 R109 33.2 K 1 % 1/8 W 50 ppm 523839L00 R 101 TO R 109 RESISTOR NETWORK 682638-79

A101 100 K 20 % SINGLE TURN CERMET VA 05 V 522956E00 A102 22 K 20 % SINGLE TURN CERMET VA 05 V 522956D00 A 103 50 K 10 % MULTITURNS CERMET 523108J00


24


4/21/2005

C101 CAPACITOR 220 F 16 V CHEMICAL 523124B00 C102 CAPACITOR 2200 F 16 V CHEMICAL 523096K00

E101 90 V DISCHARGER 524540A00 FUSE FAST ACTION FUSE 6 * 32, 0.315 A/ 660V 100.429

HIGH VOLTAGE BOARD ASSEMBLY #679299-95

R201 100 K 5 % 1/5 W CARBON 522697P00 R202 a 2.37 M 1 % 1/8 W 50 ppm 524624D14 R202 b 2.37 M 1 % 1/8 W 50 ppm 524624D14 R202 c 2.37 M 1 % 1/8 W 50 ppm 524624D14 R202 d 2.37 M 1 % 1/8 W 50 ppm 524624D14 R203 249 K 1 % 1/8 W 50 ppm 524068A00 R204 150 K 1 % 1/8 W 50 ppm 523886V00 R205 49.9 K 1 % 1/8 W 50 ppm 523803E00 R206 10 K 1 % 1/8 W 50 ppm 523087G00 R207 15 K 0.25 % 1/8 W 25 ppm 524986K00 R208 2.4 K 0.25 % 1/8 W 50 ppm 524986E00 R209 22.6 K 0.25 % 1/8 W 50 ppm 524986J00 R210 a 3.74 M 1 % 1/8 W 50 ppm 523839J00 R210 b 3.74 M 1 % 1/8 W 50 ppm 523839J00 R21O c 3.65 M 1 % 1/8 W 50 ppm 524624B00 R 201 to R 210 RESISTOR NETWORK 682640-79

R211 100 K 5 % 1/2 W CARBON 521586L00 R212 2.67 M 0.5 % 1 W 50 ppm 523585R00 R213 294 K 1 % 1/8 W 50 ppm 523886E00 R214 47 K 5 % 1/5 W CARBON 521549U00 R215 47 K 5 % 1/5 W CARBON 521549U00 R216 100 5 % 1/2 W CARBON 520996T00

C201 CAPACITOR 0.1 F 1600V 20 % POLYESTER 523058L00 C202 CAPACITOR 1 F 250 V 20 % POLYESTER METAL 522324F00 C203 CAPACITOR 1 F 100 V 10 % PLASTIC 524121U00

CR201 DIODE BAY 25 (2000V-100 mA) 524541A00


25


4/21/2005

MECHANICAL PARTS LIST

DESCRIPTION for MODEL 1000N PART # SCREW: C M3X6 524087-57 SCREW: M3X8 485503108 SCREW: C M3X25 485103325 SCREW: C M3X10 487103610 SCREW: C M4X16 485104316 LOSSPROOF SCREW: M3X8 677941-54 SIM SCREW: 0 2.84X6.4 521166D57 WASHER: 0 3.2X6X0.5 358027K57 WASHER: 0 3.2X6X0.5 358046G57 RUBBER WASHER: 0 3.7X8X1 358040D03 WASHER: 0 2.6X4.5X0.5 358018F03 WASHER: 0 6.2X12X0.5 358083D57 SPRING WASHER 320546-51 STAR WASHER: DE3 520569C40 NUT: HM3 461030157 WASHER: 0 3.2X6X1.5 358027U03 WASHER: 0 3.2X6X1 358027V57 TRUARC RING: 0 5 520099G00 POST 671850-57 POST 674333-57 POST 679451-57 INSULATING POST 679438-19 SPRING for CAP 679410-00 ASSEMBLED BATTERY COMPARTMENT 679431A73 ASSEMBLED SUPPORTING LEG 004204-40 FEET 004787-96 HIGH VOLTAGE SWITCH 679296-95 HIGH VOLTAGE BOARD 679299-95 HV SWITCH - BLACK KNOB 679435-96 MEASUREMENT BOARD 679298-95 MAIN BOARD 679473-93 MAIN BUTTON - BLACK KNOB 004156-96 ROTARY ASSEMBLY 679423-00 ROTOR 679424-18 METER MOVEMENT / GALVANOMETER 679433-90 PLASTIC PLUG - MALE 679428-19 CONNECTOR FEMALE 682789D90 SAFETY SOCKET (GREEN TERMINAL) 524385D00 SAFETY SOCKET (BLUE TERMINAL) 524385E00 PRESSURIZED BATTERY CONNECTOR 524031-00


26


4/21/2005

BATTERY HOLDER 524334-00 RING 670201-96 FLAT CABLE (connection between boards) 525090-00 FACEPLATE 686803-82B

PREVIOUS MODEL 1000 - DESCRIPTION PART #

COAXIAL PLUG 522615-00 FACEPLATE 679502-90 LOCK WASHER 520569C40 RING 670201-96 SOCKET 360806-54


27


4/21/2005

VOLTAGE LEVELS AND OSCILLOGRAMS FOR PROPER OPERATION Unless otherwise indicated, all of the potentials cited herein are direct potentials measured with respect to ground. The respective oscillograms correspond to a situation where the instrument is set at the 500 V / MΩ position with +P =12 V. All bold face numbers represent test points on the schematic.

1. + 5 V ± 5% - Pin 8 of Z3 2. - 4.6 V ± 10% - Pin 5 of Z3

3. + 2.49 V ± 4% - Pin 1 of Z1 3b. - 1.65 V ± 5% - Pin 8 of Z2

2.6 V

0 0 0

11 V 26 V

12 V

4. 5. 6.

7. + 50 V to + 1000 V, according to selected

range ± 5% + 1100 V ± 5% in KΩ position (1 mA)

8. + 2.49 V ± 4% 9. + 2.49 V ± 5% if KΩ range is selected 10. For any MΩor GΩ range which is

selected and with a voltage level of 50 V to 1000 V, one should obtain at pin 10 of Z5:

1 MΩ input: 4 V @ 5% 10 MΩ input: 0.4 V @ 5% 100 MΩ input: 40 mV @ 5% 1000 MΩ input: 4 mV @ 5%

11. V (pin 4 of Z6) - V (pin 8 of Z6)

4 V at pin 4 ≈ - 50.7 mV at pin 8 0.571 V at pin 4 ≈ 0 V at pin 8 0.4 V at pin 4 ≈ + 9.3 mV at pin 8 40 mV at pin 4 ≈ + 69.3 mV at pin 8

4 mV at pin 4 ≈ 129.3 mV at pin 8 12. V [pin 8 of Z6]-V[pin6 of Z7]

- 50.7 mV at pin 8 ≈ 0 V at pin 6 + 129.3 mV at pin 8 ≈ 1.5 V at pin 6

13. Voltage at terminals of CR3 is

2.49 V ± 4%, Current for Ω measurement: 10 mA

14. + 11 V except on ranges for measuring

between 0 and 200 Ω: - 0.2 V

0 0

12 V12 V

15. 16.


28


4/21/2005

MODELS 1000N/5000N POWER SUPPLY

Specifications

Open Voltage: 10 V ± 5%

Output Voltage at Max Load: 9.4 V ± 5%

Max Load: 350 mA

Ripple: < 2% Peak to Peak

Supply Variation: 110 V ± 15% or 220 V ± 15% (45 Hz to 70 Hz)

Dielectrical Test: 4000 V AC 50 Hz 1mn or 6000 V DC

Protected By: 1 Fuse 5 x 20 mm

Power Supply

F1

CR1

C1

CR2

Rd.1

10V/350mA

Power

Q1

R1

T1

K1

110V

220V

+

Parts List

R1 220Ω 1/2 W 5% 520996Z C1 1000 µF 40 V Type CMF-FP 523865G CR1 WS 005 Rectifier 50 V - 1.5 A 523017D CR2 BZX 85C 10 Diode 10 V - 1.3 W 522754G Q1 TIP 31 C NPN 523675S T1 Transformer 110 V / 220 V 679556 F1 Fuse 5 x 20mm 0.1 A / 250 V 524132U Fuse Clips 529076 K1 Sliding Switch 523892


29


4/21/2005

F1

+ 2

2 CR

1

K1

T1

Q1

C1 C

R2

R1


30


4/21/2005

MAIN BOARD 679473-93

R46

R43

R44

R45R47

R3

Q3

C3

C4

Q4

C5

C18

C1

Eb

Ec

CR3

Q2

R

I

E

Q

T

KK

S

S

Y

U V

J

D

F

CR25

R55R23

R22

R42

R15

R32

R35

R27

R13

C9

R53

R31

R30

R28

R29

R24

R14

R56

R38

R39

R36

C13

R26

C12

R59

R5

R6

R1

R49

R57

C6 C7 A1

R2

R52

R20

R41

R40

R9

R10

R12

C17

C16C14

C10

C13

R11

R34

R54

R4

R58

R51

R50

R60

R48

R7

R21

R16

R33

R19

R18

R17 C19

R8

A1: SHORT CIRCUIT ADJ.A5: 100 MΩ ADJ.

A2: END OF SCALEOHMETER

A4: 1 MΩ ADJ.

+

+Ð

Ð

Z3

C8

Z8

A4

Z7

Q1

C2

A2 A5

CR1

CR4

CR8

CR12

CR2

CR10

CR11

CR6

CR7

CR13

CR5

Z6

Z1

Z2

Z5

CR15

CR14

R37

A3

Z4

A3: 0.1Ω ADJ.

POINT D = ONE OF THE BOTTOM

SCREWS ON THE HV SWITCH

SHORT CONTACT

+

+

+

+

Ð

Ð

Ð+ Ð

+

+

NOTE: Z4 and Z7 were replaced by OP07C

Remove C9 and C20


31


4/21/2005

MEASUREMENT BOARD 679298-95

A

10

3

A102

R109

E1

01

R101

R102

R104

R108

R107

R103C

R103E

R103A

R103B

R1

05

R1

03

D

R1

06

R101A

C102

C101

FU

SE

SHORT CONTACT


32


4/21/2005

HV BOARD 679299-95

R201

C201

C202 R211

R216

CR201

R214

R215

C203R213

A

A

Short Contact

Clear Wire (short)

Green Wire toGreen Terminal

Clear Wire

Clear WireFrom Switch

R2

10

C

R2

07

R2

06

R2

05

R2

04

R2

03

R2

02

D

R2

02

A

R2

02

B

R202C

R2

10

A

R2

10

B

R208

R209

MODEL 1000N MEGOHMMETER CAT. #185.100

33


4/21/2005

B1-B8

8 x 1.5V

A-W C

C102

2200 µF

Measurement Board

BP1

B-X D

+B

R14

R15

7.5M

470K

C8

1µF

Z8

8

7

6

2

1CM7555

4

1

3

R54

100K

CR12

BAT42

R16

10M

Z2d7

5

6

1/4 TL 084 R19

100K

150K

R17100K

+ 5VR18

A2

47Ω 100ΩR23 Q2

BD52CR4 R24

470Ω1N4002

R25

4.7KCR3

LM 336

R1

3.3

K

R2

18K

A1

2.2K C1

1µFR3

1.5KCR1

LM 336R4

100K

Z2a

1/4 TL 084

15K

R10

R9 10K

9

10

8

R39

1KR7

22KC2 C3

1µF

Z1 TL 495

15 12 11 8 2 3 17 16

18 7 5 6 14 1 9 10

C4

0.1µF

R518 K R6

1K

R8

150Ω Q1

TIP31C

E

T1

CR2

1N4DC2

HS1

E1

E2

F

S2G CR201

S2

C201

0.1µF

R216100Ω

100Ω

100Ω50Ω

50V 100V 250V 500V 1000V

50V 100V 250V 500V 1000V

C2021µF MΩ GΩ

MΩ GΩ MΩ GΩ MΩ MΩ GΩ MΩ GΩ KΩ

MΩ GΩ MΩ GΩ MΩ GΩ MΩ GΩ MΩ GΩ

MΩ GΩ

R211

KΩ

High Voltage Board

150K250K9.5M 50K 10K 15K 2.4K 22.6K

R204R203R202 R205 R206 R207 R208 R209

j

R204100K

R210

M

KNR214 R215

47K 47K

R212

2.67M

C2031µF

R213294K

M

K2h

K1 K3

R11

24.9K 12

1314

R12249K

Z2b

l 1/4 TL 0841N4148

CR8

m

e

f

1mAQ

h g

31

7

6

84

2Z4 LM 308 R

C9100pF

+B

CR5

1N 4148CR13

R13240K

i

C510µF

Z31CL7660

2

4

3

5

8

C710µF

C610µF

+ 5V

+ P

- 5V

(9V to 12V)

+P

R20100K

R552.2K

Q3BC 307B

R2210R

R21

22K

I

J

Bz1

S

CR7

R260.09Ω

- 5V

+ 5V + 5V + B

- 5V

+ B

R27

1K

BZV.15V

A310K

Z2c

1/4 TL 084

R30

3

2

4

1

1M

11

R29100K

R2840.2K

R3149.9K

R53

22K

CR610V

R32

22K

1mA

+ B

R331K

CR9

Q4BC 184C

Ω

Main Board*Changes on New Board (525112V00A)

Q2 - BD 140 (80V - 1.5A)

C9 - Not Used

Common

Ground

A1: Short Circuit

Current Adjustment

A2: End of Scale Ω

Jumper

1

2

A3: 0.1Ω Adjustment

15

16

3

4

5

6

7

8

9

13

14

4


Remove C9 and C20

MODEL 1000N MEGOHMMETER CAT. #185.100

34


4/21/2005

R34

47Ω+ B

P

F101

0.315A

L

E101

90V

Ω

R36 R37

C11 C12

499K 499K

0.33µF

C1010µF

Y

C1322nF

C1410µF

R35

47Ω- 5V

R38

1M

Z5115 9

4

7

18 2 10

1CL7650

C15 4.7nF

C16 C17

0.1µF 0.1µFT

R56

10.2Ω

A4

200K

R39

4.02M

CR14

CR15

R40 R41 R42

R57

59K

100K 178K 178K

Ea Eb

C181µF

Rad. 1

R582.37K R48

499ΩZ6

AD536

6

6

8

3

3

7

7

1 2

2

9

4

4

8

5

U V

C19

Th1TSP 102(1000Ω)

Z7

+ B

- 5V

- 5V

C20100pF

LM308

A5R49

2.2K8.87K

4.42K

R52

BP2

G1

0.1µF

R60100K

CR101N4148

CR111N4148

R5110K

R5010K

1mA

KΩGΩ

1000V500V250V100V50V

MΩGΩMΩGΩMΩGΩMΩMΩΩ

R43 R44 R45 R46 R47

1K 1K 3K 5K 10K

GΩMΩ GΩ GΩ GΩ GΩ KΩMΩ MΩ MΩ MΩ

1000V500V250V100V50V

R10136.2K

1mA

R1034.02M

R1023.92K

R106R105

1M1M

R108402Ω

R107100Ω

+ 5V- 5VA103

50K

A102

22K

R109

33.2K

R104

2.4K

d

- 5V

A101

100K

+ 5V

a b c

- 5V + 5V

R

C101220µF

A5: 100 MΩ adj.

(MΩ scale)

Measurement Board

L

A

a

electrical shielding

mounting post connection

mounting wire or terminal

flat cable connection

A101: zero adj. for Z5

(MΩ scale)

A102: 1000 MΩ adjustment

A103: zero adj. for Z5

(GΩ scale)

A4: 1 MΩ adj. (MΩ scale)

*Changes on New Board:

Z4 and Z7 (OP 07C) 019S0002000000

C20 - Not Used

10

11

12


Remove C9 and C20

megohmmeter model 1000n - userequip.comuserequip.com/files/specs/5090/1000_serv-man.pdf · the...

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