ECN Forum Forums General Topics of the Trade General Discussion Area Arc Fault Circuit Breakers

Hi Ann Bush,
As an inspector/contractor is a copy of your data sheet available to the public?

Ken

After some reflection on what I said on the thread and some of the questions that followed I have learned that the decision to write what I did was a bit rash. In any controlled experiment there are numerous factors that need to be adequately communicated in order to interpret the data properly. In this instance I have commented on the results but cannot provide any of the conditions that generated them, as such none here are able to draw their own conclusions and I have done you all a disservice. I have deleted my original posting. Please accept my humble apologies and understand that I cannot comment further. This was not well thought out on my part.

I have some ideas, but since reno was nice enough to start a new thread here
I will make my comments there.

Ann, I completely understand, and regret it if anyone (including myself) 'pushed' a bit hard. One must listen to the BOSS sometimes ... and there are often details that can get in the way of a clean report.

This may have been covered in one of the other posts but lots of guys seem to jumping on the arc fault wagon whether required by code or not. My question would be 'isnt the effectiveness of the arc fault or gfci breaker compromised when they are not tested regularly?' So how many homeowners do a monthly trip test on them, even after you have carefully gone over the procedure? So you can say they can save lives, but if you want to start throwing them in everywhere, is there any data on age of breaker/effectiveness of protection and if they were regularly tested? Code is code, and we are required to follow it, but if fault protection is only ensured with regular testing, maybe some new rules or new product needs to be considered.

Jay,
Yes, because these devices are not fail safe. You can lose the arc fault part of the breaker and there is no indication and the breaker continues to supply the circuit with power. At this point the breaker becomes a standard thermal magnetic breaker.
Don

What would the inrush current be on a 15amp miter saw? My guess is probably more than 75 amps. I know that with the one that I have, (a large DeWalt unit) the inrush current is pretty strong.

They also look at the shape and frequency of the spikes. I doubt one big startup spike would do it. Maybe if your switch was bad and it saw LR current a few times real fast it might trip. One of my neighbors (Harvey Johnson) worked on the early development of AFCIs for Cuttler Hammer. I know they spent a lot of time looking at the difference between an arc fault and other large current transitions.

Had my first experience with an ark fault problem that was not a simple ground touching neutral or mixed up neutrals, the other day. Traced the problem to a loose compact fl lamp in a recess can. The screw in type lamp that looks like a twisted ice cream cone. Once I tightned up the lamp the problem went away and the circuit breaker was able to hold the entire load of the circuit ok. This was no ground fault situation, but rather an ark of sorts. I say of sorts, since the ballast for that lamp is in the base. Must have looked like an ark to the breaker.

That's exactly how I go about doing electrical work. Making people feel safe, IMO, is a part of our job. But since ARC-FAULT circuit breakers are NOT REQUIRED in the state of New Jersey, I've yet to install one. But I do have a bunch of them on the truck from a modular home job that where we never used them, nor were we required to use them.