afcicircuit breakerelectricalsurge-suppression
I have a problem with AFCI breakers tripping in my 2 and a half year old house. The builder's electrician said that the cause is from power surges coming from the electrical company and that I need to get a surge protector put in at the service.
The breakers are Sqaure-D QO120 single pole plug on neutral. When the trip its about 7 or 8 of them the frig, microwave, dryer, some plugs when the laptop is plugged. This usually happens when it's raining or damp out.
I've had some issues with AFICs in the past, and one quick thing you should check (which ended up being my problem): Is the insulation on the wire coming into the outlet box pinched and causing a loose/flaky connection? That will still give power to the outlet (under a normal breaker) and won't trip a normal breaker, but it'll drive an AFCI nuts.
Another technique you can try to debug this is by swapping in a GFCI breaker, and see if that trips too. If the GFCI trips, it's a grounding problem. If it only trips on the AFCI, then there's arcing somewhere along the circuit. Check junction boxes, the outlet boxes and the connections to the plugs in the boxes.
Happy & Safe Debugging!
Some surge protectors work by "redirecting" surges to the equipment ground, which is pretty much the definition of a ground fault. In this case, it's definitely possible that surge suppressors could be tripping GFCI receptacles/breakers (given a large enough surge).
As for the AFCIs... When electrical contacts separate, they often create an arc between the contacts. This arc spans the gap until the contacts are too far apart, and the arc can no longer be sustained. It's possible (in theory) that the GFCI tripping could create a large enough arc, for long enough to cause the AFCI to trip. It's not likely that a properly functioning GFCI would do this, but if the GFCI was old and worn it could be opening the contacts slow enough that a detectable arc is being produced.
Determining if the GFCI tripping is causing the AFCI to trip, is a simple test. Simply press the test button on the GFCI. If the AFCI trips, you'll have figured out half the problem. If the ACFI does not trip, you could repeat the test using a receptacle tester with a GFCI test function.
If it's determined that the GFCI is causing the AFCI breaker to trip, replacing the GFCI receptacle may resolve that part of the issue.
Figuring out if the surge suppressor is tripping the GFCI, is a more difficult proposition. It will likely require you to monitor the supply voltage over some time, to identify and document possible surges.
Best Answer
The job of AFCI is to protect the house from series or shorting arc faults, which cause fires.
The main reason AFCI breakers are required today is because so many houses are built with backstab connections to switches and receptacles, and those so often fail in a series arc fault mode.
Keep in mind, the builder's electrician is the one who wired the place. So the last thing he's going to say is "it's tripping because I used backstab connections when wiring your house because I was in a hurry, and one is failing as they often do. Sure, I'll do a go-back and spend two hours taking apart all your receptacles and moving the wires to the screws, or fitting the $3 receptacle instead of the 60 cent one".
That said, it can also be a failing appliance. However if you move the appliance to a different AFCI protected circuit, this circuit will stop tripping and that circuit will start.