I just finished a new panel installation and the utility company just energized it. I completed the wiring for one circuit with a 20A AFCI breaker, when I plugged in an incandescent light the breaker tripped. I tried several other devices and the breaker kept tripping. The circuit has 2 receptacles, first is 4' from the panel and the second is 8' from the first one. I then wired a second 12' long circuit using a 20A GFCI with 1 receptacle on it with the same results. The utility voltage may be high. Could that be the cause?
- Get a wiring tester and verify the GFCI outlet is wired correctly.
- Swap out he 20A AFCI breaker for a standard 15A or 20A breaker and then see if the GFCI outlet works after that.
- Use a multimeter at the GFCI outlet to see if the voltage is in the expected range.
- Post photos of wiring at all locations so we can better help you.