Ground fault interrupter replacement

The ground fault detector and interrupter (GFDI) is the inverter's protection device for ground faults on the PV DC side, and this action replaces its interrupting element after it has operated or failed. In systems with negatively grounded modules, the negative PV cable is tied to the grounding system inside the inverter, and a ground fault in the DC wiring makes the inverter disconnect from the grid. One documented GFDI is designed to trip at 240 mA of PV ground current, with a tolerance of 40 mA either way, and shows ground faults on the inverter control panel. With a fuse-type grounding device, a sudden, strong residual current blows and destroys the fuse, while the inverter itself detects slower, lingering residual currents. Find and clear the ground fault first. Then inspect the grounding fuse and replace it if needed with the part the manufacturer specifies. If the ground fault is cleared in time, the fuse may not be destroyed, so an early response can avoid a replacement. Replacing the part does not remove the cause, so keep ground fault detection running at all times and inspect the system regularly.

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• sentence 1: support check: partial - Passages describe GFDI as ground-fault protection/disconnect on DC side, but nothing about an action replacing its interrupting element after operation or failure.
• sentence 7: support check: partial - u3 supports continuous ground fault detection and regular inspections, but not the claim that replacing the part does not remove the cause.
• sentence 1: review: partial - The passages describe the GFDI as DC-side ground-fault protection that disconnects the inverter, but nothing in them says this action replaces its interrupting element after it has operated or failed.
• sentence 7: review: partial - The IEA row supports ground fault detection at all times and regular inspections, but not the claim that replacing the part does not remove the cause. -->