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High Ground Current Alarm
The following summarizes some of the possible causes and solutions for heat tracing high ground current alarm.
If issues remain after exercising all these possible causes and solutions for heat tracing alarms and trips, contact your
nearest Thermon engineering center for assistance and/or for arranging for field service.
Possible Cause
Recommended Solutions
Heat tracing is damaged.
Disconnect heat tracing circuit and determine if alarm clears. If so, repair
heat tracing.
Wiring to heat tracing had high
leakage current.
Disconnect heat tracing and sequentially disconnect power wiring until the
alarm ceases. Check last section removed for damage.
Improper wiring of current sense wires
through toroid.
The current sensing toroid must have the outgoing heater current lead and
the return current heater lead run through the toroid for a proper ground
leakage measurement. Redo wire routing if only one wire has been run
through the current sensing toroid.
Heat tracing power wires in a multiple
circuit system improperly paired.
If the return current wire in the toroid is from a different circuit the two
heater currents will not cancel and leave only leakage to be measured.
Correct wiring.
Heat tracing circuit has higher than
expected leakage due to circuit length
or higher voltage.
Replace the EPD breaker with a higher ground current trip device if
available. Where a controller (with variable leakage trip functions) is doing
the ground leakage detection function, increase ground leakage alarm set
point (if approved by project engineer).
