Multilin SR469, Instruction Manual

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2. INSTALLATION ELECTRICAL
2-19
2.2.15 DIELECTRIC STRENGTH TESTING
It may be required to test a complete motor starter for dielectric strength (“flash” or hipot”) with the SR469 installed. The SR469 is rated
for 2000Vdc isolation between relay contacts, CT inputs, VT inputs, trip coil supervision, and the safety ground terminal G12. Some
precautions are required to prevent SR469 damage during these tests.
Filter networks and transient protection clamps are used between control power, trip coil supervision, and the filter ground terminal G11.
This filtering is intended to filter out high voltage transients, radio frequency interference (RFI), and electomagnetic interference (EMI).
The filter capacitors and transient suppressors could be damaged by application continuous high voltage. Disconnect filter ground termi-
nal G11 during testing of control power and trip coil supervision. CT inputs, VT inputs, and output relays do not require any special pre-
cautions. Low voltage inputs (< 30V), RTDs, analog inputs, analog outputs, digital inputs, and RS485 communication ports are not to be
tested for dielectric strength under any circumstance (see Figure 2-27).
Figure 2-27 TESTING THE SR469 FOR DIELECTRIC STRENGTH