How to troubleshoot a ground fault error on a Schneider Electric Xantrex GT Inverter?
Important Note: Troubleshooting Schneider Electric Xantrex GT Inverter faults including ground faults must be undertaken and completed by a CEC - Grid Connect Inverter accredited solar installer/service agent. This is a safety requirement as failure to follow installation instructions could result in death or serious injury in addition to voiding terms of the warranty.
Complete the ground fault troubleshooting section of the attached site troubleshooting checklist.
Additionally, the isolation impedance of both the positive leg to earth and negative leg to earth can be measured using a minimum 600VDC rated multimeter.
The inverter should be powered down and the DC inputs disconnected to obtain an accurate isolation impedance reading.
Both the positive leg to earth and the negative leg to earth should be greater than 500kOhms. If they are displaying greater than 500kOhms then the ground fault error is being caused by a faulty inverter.
If you are measuring less than 500kOhms on either the positive leg to earth or the negative leg to earth then you will need to inspect your PV panels, wiring, isolators, breakers for moisture and wiring issues which could be resulting in the ground fault condition.
If you have an external earthing kit installed as required by your PV panel manufacturer then the internal ground fault protection of the Xantrex GT Inverter should have been disabled.