Megger ADX15, Руководство пользователя

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NOTE: Ramp rates over 50V/pulse are not recommended for PD detection.
4. Define the (PD) Ramp Down Voltage—a “lower target” level at which PD detection is not expected (so the system
does not have to ramp down to 0 volts before ending the test). This setting also minimizes the effect on PP EAR
while ramping down.
5. Check the PD Enabled box and enter values for PD Threshold and PD Event Limit.
„ PD Threshold—the amplitude at which a high-frequency transient (PD Event) is counted towards the PD Event
Limit.
„
PD Event Limit—the cumulative number of PD Events during each surge pulse required to constitute a PD surge
pulse. When the number of PD Events exceeds this limit, a PD surge pulse is detected.
Fig 115: Surge Test section in test configuration Editor screen.
NOTE: The PD Time Scale value shown above adjusts the display so that you see only one microsecond
of the high-frequency content. Zooming in on the front edge of the surge waveform helps you see the
region where PD activity is most likely to occur. The activity shown is more representative of what the PD
event counter displays.
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Megger Baker ADX User Guide
117
Surge Testing with Partial Discharge