Afci circuit with gfi extension cord?

[chuck b]

Hi! I have rewired my enitire 800 sq. ft. cottage to code. Interior non-GFI protected circuits are wired on breaker AFCI's (non bathroom, kitchen, laundry, exterior circuits). I am thinking that when I use hi amp power tools I could benefit from connecting to an AFCI protected circuit, when using them with a GFI protected extension cord. Make sense? Thanks.

[kreemoweet]

High-amp power tools are notorious for causing nuisance trips on GFCI devices. If you use 'em, be prepared
to push the reset button every two minutes.

[cacher_chick]

I'm not sure I see any need for having such protection, but there is nothing wrong doing it, and it will work.

[Speedy Petey]

I am thinking that when I use hi amp power tools I could benefit from connecting to an AFCI protected circuit, when using them with a GFI protected extension cord.

I am very curious as to why you think this.

[chuck b]

Guess the GFCI makes sense, but are you saying that the AFCI usage is in question? I did not mention that the wires for the AFCI are not new, and I am concerned that until I get the chance to take down walls to expose them and put in new romex, they could overheat, arc.

[jadnashua]

You said you did things to code, so, that means that you didn't put heavier gauge receptacles or other things on wire that was too small. There should be nothing to overheat. The only time you might overheat wiring is with bad connections, or using too small wire for the protection (i.e., circuit breaker).

[hj]

Circuit breakers are sized to protect the wire. If the wire overheats you used the wrong circuit breaker for it and it SHOULD be changed until the wire is upgraded.

[jadnashua]

You can use heavier wire than the minimum, but you can never use wire that is smaller than the minimum for the protection device, the circuit breaker (as long as you stay within the range of acceptable wire for the device- i.e., it has to be able to fit in the clamp or screw). As long as you do that, there should never be any overheating...the protection device would trip first.

[ActionDave]

High-amp power tools are notorious for causing nuisance trips on GFCI devices. If you use 'em, be prepared
to push the reset button every two minutes.

What power tools? How many Amps? I can't imagine any power tool that plugs in to a 120V recpt that would draw more Amps than a hot tub and they are all GFCI protected.

[jadnashua]

I'm guessing here, but I would guess a brush type motor where the brushes are getting old (and maybe not!) might give an AFCI a workout. If you've ever looking through the cooling vents, it's likely you could see all sorts of sparks occuring. It probably wouldn't unbalance a GFCI, but might an AFCI. Don't have any AFCI in my (older) place, so can't experiment without costs, and I'm not up for that at the moment.

[cacher_chick]

I run my shop-vac, drills, saws, etc., on an AFCI circuit all the time.

It has never tripped. Yet.

[ActionDave]

I have had no trouble with motors in power tools tripping an AFCI. I have had problems with electronics making them trip, more specifically tools that have a soft start.