Ground Faults

Last modified on March 9, 2020

A ground fault is a wiring fault — a live wire is making contact with the ground. Ground faults are dangerous because they can electrify metallic parts including enclosures, metal roofs, metal siding, conduit, fences, etc. Ground faults must be fixed! People and animals can be injured or worse from ground faults. Ground faults can also start fires.

All modern solar energy systems are equipped with ground fault protection to disable the system in the event of a ground fault. However there are a number of scenarios where a ground fault can persist despite the protection system. Ground faults must be fixed!

Symptoms of ground faults:

  • Ground fault error on an inverter or charge controller, often represented as GFI, GFDI, GF Error, or Earth Error
  • Blown ground fault fuse in an inverter or charge controller
  • System not operating
  • Electric shock from touching a metal part

Sources of ground faults include:

  • Pinched, frayed, or abraded PV wire making contact with a PV module frame or racking
  • Water ingress to an enclosure
  • Rodent or other pest damage
  • Chronic wear ie hanging wires rubbing on a roof
  • Improper grounding somewhere in the system

If your system is experiencing ground faults it’s time for a thorough inspection to find and repair the source of the faults.