Troubleshooting

There are some checks you can perform to try to identify potential issues with the device’s operation.

The following table describes potential problems, their possible causes, checks you can perform and possible solutions for each. After referring to this table, if you cannot resolve the problem, contact your local Schneider Electric sales representative for assistance.

Potential problem	Possible cause	Possible solution
The device displays nothing when switched on.	No power supply to the device.	Check that the auxiliary power supply is present.
The device displays nothing when switched on.	The auxiliary power supply is not compliant.	Check the auxiliary voltage.
The device notified an insulation fault, but your system shows no signs of abnormal behavior.	The insulation alarm threshold is not appropriate.	Check the value of the insulation alarm threshold. Modify the insulation alarm threshold as appropriate.
You deliberately created an insulation fault, but the device failed to detect it.	The resistance value used to simulate the fault is greater than the value of the insulation alarm threshold.	Use a resistance value that is lower than the insulation alarm threshold or modify the insulation alarm threshold.
	The fault is not detected between neutral and ground.	Start again ensuring you are between neutral and ground.
IMD detecting fault, the device is not	The insulation alarm threshold is not appropriate.	Check the value of the insulation alarm threshold. Modify the insulation alarm threshold as appropriate.
	There are faults on the same phase on several feeders and insufficient signal to locate fault with the selected device threshold.
	Fault is on an ungrounded system location not monitored by the device, such as the bus between the branches	Check for insulation fault upstream of the device with the mobile fault location kit.
	IMD network settings not configured for compatibility with the device.	Ensure that IMD network settings is configured. See Network configuration for more information.
Device alarming but IMD not detecting fault	The insulation alarm threshold is not appropriate.	Check the value of the insulation alarm threshold. Modify the insulation alarm threshold as appropriate.
	Ungrounded system insulation may have changed over time or under different conditions.	Review insulation resistance history on the IMD and identify if its threshold needs changes.
	IMD network settings not configured for compatibility with the device.	Ensure that IMD network settings is configured. See Network configuration for more information.
Alarm relay behaviour inverted (off when should be on, or vice versa)	Incorrect relay wiring	Change relay wiring to provide the expected relay behaviour.
Alarm still on even after fault fixed	Second fault exists on indicated branch circuit (same live conductor, same feeder)	Check and correct the second fault.
Nuisance alarms	Highly disturbed ungrounded power systems with potential power quality issues	Check the value of the filtering. Modify the filtering as appropriate.
Slow device response time	The filtering is not appropriate.	Check the value of the filtering. Modify the filtering as appropriate.
The product status LED is red and the display indicates that an error occurred during the auto-test.	Internal error	Briefly disconnect the auxiliary power supply to the device.
Although the device is being supplied with power, the product status LED does not light up.	Faulty indicator light.	Restart the auto-test and check that the product status LED lights up briefly.
The alarm LED does not light up in the event of a fault.	Faulty indicator light.	Restart the auto-test and check that the alarm LED lights up briefly.