Megger ATEC 210415 Series, Руководство пользователя

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M
60
AVTM21-415Ja Rev. A June 2005
1. Make connections as shown in Figure 17 using 5 µA range
on standard meter and 100-megohm resistor.
2. Operate the test set (Reference Section 8).
3. Set voltmeter range to 7.5 kV and megohm range to X1K.
4. Increase the output voltage until standard current meter
indicates 5 µA (at almost 500 volts).
5. The Test Set megohmmeter must read 1.0 megohms
±1/16 inch.
If the required accuracy is not met, the meter or its protective
network may require repair. This must be done prior to
calibration of the X1, X10 and X100 ranges.
Next, adjust the X10 range using the MOCAL adjustment.
(This adjustment applies also to the X1 and X100 ranges).
Proceed as follows, using the 10-megohm load resistor:
1. Set multiplier to X10; standard meter for 500 µA.
2. Increase output for a current of 500 µA (at about 5 kV).
3. Adjust the test set calibrator (MOCAL) so that the
megohmmeter reads 1 on the lower scale. To make this
adjustment, remove the MOCAL cover screw, and use a
fine blade screwdriver to adjust the calibration control.
4. To check for tracking, reduce the voltage until the
standard current meter reads 0.25 mA. The megohmmeter
should then read 2.0 on the lower scale. Re-adjust
MOCAL for the best compromise.
5. To test the X100 range:
a.
Connect the 10-megohm resistor and set the current
to 50 µA (at about 500 Volts).
b. The test set megohmmeter should read 1.0 megohms.