GE Power Quality Meter Series, Instruction Manual

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GE Power Management PQM Power Quality Meter 2-21
2 INSTALLATION 2.2 ELECTRICAL
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2.2.11 DIELECTRIC STRENGTH TESTING
It may be required to test the complete switchgear for dielectric strength with the PQM installed. This is also
known as "flash" or "hipot" testing. The PQM is rated for 1500 V AC isolation between relay contacts, CT
inputs, VT inputs, control power inputs and Safety Ground Terminal 6. Some precautions are necessary to pre-
vent damage to the PQM during these tests.
Filter networks and transient protection clamps are used between the control power, serial port, switch inputs,
analog outputs, analog input, and the filter ground terminal 5 to filter out high voltage transients, radio fre-
quency interference (RFI) and electromagnetic interference (EMI). The filter capacitors and transient absorb-
ers could be damaged by the continuous high voltages relative to ground that are applied during dielectric
strength testing. Disconnect the Filter Ground Terminal 5 during testing of the control power inputs. Relay con-
tact and CT terminals do not require any special precautions.
Do not perform dielectric strength testing on
the serial ports, switch inputs, analog input or analog output terminals or the PQM internal circuitry
will be damaged.
Figure 2–16: HI-POT TESTING
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