Arc fault detected

The inverter's arc fault detector picks up the electrical noise of a DC series arc. The inverter then shuts down and shows a message such as Arc Fault Detected, ARC Protect or Electric arc detected. In monitoring data, AC output stops and feed-in does not restart until the fault is cleared manually or operation inhibition is reset. A real arc fault usually comes from damaged, pinched or abraded conductors, loose or separated connections, poor crimps, cracked or corroded solder joints, degraded junction boxes or rodent damage. Look for evidence of arcing: discolored wiring or racking, melted connectors or insulation, and burned junction boxes. Gently tug on DC cables and connectors to find loose terminations, including factory crimps on the modules. False trips can happen when light changes cause rapid current swings, but the site must still be inspected before every reset. If no array or wiring damage is found, suspect a failed arc detection board. Check that the logic connector to the arc board is secure, then run the arc fault self-test. If the alarm comes back, replace the arc board or wiring box. Some inverters report which string group detected the arc, which narrows the search to the strings on those inputs.

<!-- review notes

• sentence 6: support check: partial - Check logic connector, run self-test, and replace arc board or wiring box if alarm recurs are stated, but 'if no array or wiring damage is found, suspect a failed arc board' is only loosely implied (u23 says if no issues found contact service). -->