ASTM D 3382 : 1995

1.1 These test methods cover two bridge techniques for measuring the energy and integrated charge of pulse and pulseless partial discharges:

1.2 Test Method A makes use of capacitance and loss characteristics such as measured by the transformer ratio-arm bridge or the high-voltage Schering bridge (Test Methods D150). Test Method A can be used to obtain the integrated charge transfer and energy loss due to partial discharges in a dielectric from the measured increase in capacitance and tan [delta] with voltage.

1.3 Test Method B makes use of a somewhat different bridge circuit, identified as a charge-voltage-trace (parallelogram) technique, which indicates directly on an oscilloscope the integrated charge transfer and the magnitude of the energy loss due to partial discharges.

1.4 Both test methods are intended to supplement the measurement and detection of pulse-type partial discharges as covered by Test Method D1868, by measuring the sum of both pulse and pulseless discharges per cycle in terms of their charge and energy.

1.5 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use. Specific precaution statements are given in Section 7.