Troubleshooting AFCI Ckt

[kwired]

I haven't been living under a rock but I haven't heard of this breaker. We have to use the brand that fits the panel. Homeline panels were installed long before we got the job.

What brand is this trip code breaker? Maybe we could set up a test box of some sort with it.

Most (if not all) new breakers have diagnostic features now. Siemens, and BR have indicator lights, Not sure about GE, Square D QO and Homeline are the same - you press and hold the test button while turning the breaker on - how many seconds until it trips is what you need to look for. Can't remember for certain but I think if it trips immediately - that indicates ground fault, two seconds means it tripped on AFCI feature, might be other indications at three or four seconds, and seems like if it lasts for five seconds that means there is no fault code in memory.

Thanks for the feedback but I can't buy neutral/ground short. If that were the case, the breaker would never hold to begin with. We fixed a few of these in neighboring apartments.

GFCI's inject a signal onto the conductors to help with detecting neutral to ground faults - no (load) current needs to be flowing to detect these faults, just a current from the injected signal. (I think this might even be part of listing requirements for GFCI's) This is why a GFCI trips when you touch the neutral load terminal to ground even with no active load. The ground fault component in an AFCI breaker doesn't necessarily have this feature. Without that feature there must be current flowing or it will not trip. Turning on other loads is what introduces that current as it flows from the faulted neutral to the EGC.

 

[romex jockey]

I'm sorry Mr Kwired,

but i do not subscribe to some sort of belief system when it comes to electrical theory, not should UL1699 be nefarious enough to spawn them.

this is why the whole afci debacle survives

~RJ~

 

[mbrooke]

We finally found a switch leg to a bath fan with an overdriven staple. That took care of it. I was happy to get it working but still wonder how hitting other switches would make a difference. Too many mysteries sometimes.

If the over driven staple caused a neutral to ground short, then as previously explained load eventually pushed the AFCI past its 30/50ma GFP threshold. Its not mystery when you learn how it works.

 

[kwired]

I'm sorry Mr Kwired,

but i do not subscribe to some sort of belief system when it comes to electrical theory, not should UL1699 be nefarious enough to spawn them.

this is why the whole afci debacle survives

~RJ~

??

All I said was that most new breakers now have a diagnostic feature to tell whether they tripped on GFCI or AFCI sensing function of the device, I wasn't suggesting anything for or against AFCI protection in general.

Seems like a useful tool for troubleshooting whether you like AFCI's or not.