Put an AFCI on a ckt going into a bedroom just like the code calls for. Tripped immediately when I powered up.
I took apart the box, freed up all wires, that my hot goes into first in that room (home run should have then been attached only at the AFCI). Still tripped.
Next I swapped out the AFCI w/ a regular breaker. Works fine.
What are my steps in troubleshooting this? Will swap out for known working AFCI first and if it still trips I guess I may need to consider tracing my hot feed to panel and perhaps replacing it?
Help?
Replies
Try it on another circuit. Possible defective AFCI or defective wiring and the AFCI is acting normally. If you had another AFCI you could try installing it on the original circuit and see what it does.
AFCI are more complicated than other types of breakers and complication implies more opportunity for defects to creep in. That is just the nature of things. If you buy one keep the receipt.
I recently installed an Arcfault on an existing circuit that I added an outlet to and I had a similar problem. I undid everything I had done and redid it - still no joy.
I then read the technical notes on the Square D website (should have kept the package!). If there is any connectivity between neutral and ground it will trip. After metering the segments, it turns out an existing ceiling fixture had a short between N & Gnd. With that fixed, it worked fine.
Hope this helps.
Andrew
pardon my ignorance... how does this apply when the neutrals and grounds are all tied to the same buss bar in the panel?
It connections between the ground and neutral AFTER the AFCI or GFCI.
AFCI = Arc Fault Circuit Interrupter
The are two types of arc faults: series and parrallel. And example of series is when a wire is cut but the ends are very close together, almost touching. The current leaps across the gap in an arc. An example of parrallel is when the hot and the neutral or ground are too close, almost touching, and again the current arcs across the gap. The arc can get very hot and start fires.
AFCIs are a sham. They have a secret GFCI built into them which detects any leakage* from the hot to ground. [A fault from hot to ground seems more likely then a hot to neutral fault since the neutral is insulated with white plastic.]
To answer your question, the neutral and ground must be connected only at the panel. If they touch after the AFCI some of the current will return on the ground wire thus resulting in a lower current on the neutral which won't balance the incoming current on the hot wire which upsets the GFCI mechanism causing it to trip.
~Peter
*A regular GFCI trips around 5 nilliamps. The GFCI in a AFCI trips ~30 milliamps.