Ground Fault and Ground Continuity – Protection Panel GFGC
6 GFGC_D00395_00_D_XXEN/05.2019
Installation troubleshooting tips
• The ground fault alarm trips instantly on a consistent basis.
Near-instant tripping may also indicate a serious ground fault in
the system.
Ensure that the following items are correct:
– The transformer and contactor are wired properly per the
above wiring diagrams based on the voltage being used.
– All phases (including the neutral if one is being used) are going
through the WN-35BS current transformer. Improper wiring
can cause an incorrect reading on the ground fault detector.
– The ground conductor must not pass through the current
transformer.
– There are no neutral-ground bonds downstream of the de-
vice. Having a neutral-ground bond downstream of the de-
vice will activate the grounded neutral protection alarm.
The panel must be reset manually via the door-mounted RESET
button in order to clear the trip.
• The ground fault alarm trips on a consistent basis, but not
instantly.
Ensure all of the above items are correct.
Ensure there are no ground faults on the system. A non-instant
trip is an indication that the total leakage current from many
different sources is adding up to approximately 6 mA. Consult
the manufacturer for more information and technical support.
• The open ground alarm trips on a consistent basis.
Ensure that the following items are correct:
– There is a proper pilot wire connection to the connector on
the outside of the enclosure.
– There is a proper connection between the clamp and the ve-
hicle/object.
– There are no broken ground connections in the system being
protected.
The panel must be reset manually via the door-mounted RESET
button in order to clear the alarm.
Installation troubleshooting tips (continued)
RCMA421H Ground Fault Monitor
GM420 Ground Continuity Monitor
The RCMA421H is labeled with “
I
Δn
” in the top right corner.
Possible messages displayed on the screen include:
• “X mA”: The amount of ground fault current (in mA) read by the
device.
• “E 01”: Connection alarm (consult the manufacturer if this alarm
appears).
• “E 02”: Connection alarm (consult the manufacturer if this alarm
appears).
If the RCMA421H has gone into the alarm state, and is not display-
ing an error code, follow these steps to retrieve the mA value:
• Hold the MENU button for > 1.5 s to enter the main menu.
• Press the down-arrow button until “HiS” (history) is reached.
Press the enter/MENU button.
Use this value to assist in determining the source of the ground fault.
If any error codes appear on the unit, consult the manufacturer for
more information.
The GM420 is labeled with “Ω LOOP” in the top right corner.
Possible messages displayed on the screen include:
• “X Ω”: The resistance of the loop in ohms.
• “OL”: Overload alarm (open connection).
If the GM420 goes into the alarm state, a reading of “X Ω” generally
indicates a present, but faulty ground connection. A reading of
“OL” generally indicates a nonexistant ground connection. Use these
values to troubleshoot the ground loop connection.
If any error codes appear on the unit, consult the manufacturer for
more information.
