Megger IDAX Series, Руководство пользователя

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IDAX User's Manual 70
© 2009 Megger AB
3.1 (347) Output voltage is not within specified limits
Measured output voltage is outside specified limits.
Possible reasons and countermeasures
1) Voltage electrode, Hi, is grounded:
§ check measurement set-up and disconnect ground
§ change measurement configuration if terminal of test object cannot be disconnected from
ground
2) Voltage electrode, Hi, is connected to measuring electrode, Lo or Ground:
§ check measurement set-up and disconnect measuring or guard electrodes from the voltage
electrode. Voltage electrode, Hi, must not be connected to either measuring or guard
electrode
3) High stray capacitances to ground or high capacitance of the test object:
§ lower the highest frequency used in C-file (see also Measurement variables)
§ Lower the InitFrequency in the C-file (see also Measurement variables)
3.2 (361) Overvoltage
Measurement aborted due to overvoltage detected on measuring electrode, Lo. Potential
difference between signal ground and real ground exceeds limiting value.
Possible reasons and countermeasures
1) Ground electrode is not connected to true ground:
§ connect Ground electrode to true station/substation ground
2) Transients caused by accidentally disconnected ground connection:
§ check ground connection
3.3 (364) Measured capacitances don't match
Values of capacitance measured for different configurations, the UST, GST-Guard and
GST-Ground are in disagreement.
Possible reasons and countermeasures:
1) When performing UST measurement, measuring electrode, Lo, is connected together with
Ground electrode or Lo is connected to ground:
§ check measurement set-up and make sure that measuring electrode, Lo, is connected to a
non-grounded terminal of the test object and that Ground
electrode is connected to ground
3.4 (365) Specimen capacitance below limit
Measured capacitance below limit specified in C-file by MinSpecimenC.
Possible reasons and countermeasures
1) Measured capacitance higher than 10 pF.