GFCI on load side of AFCI?

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ronaldrc

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Whats your opinion on this?

Since the AFCI circuit that feeds the bed room circuit can leave the bed room and feed other loads, do you see a problem with maybe putting one of the outside GIF recpts. on it?

This will be a nuisance because when you test the outside GFI recpt. it will trip the AFCI in the panel.

I would just say theres going to be a lot of short service calls paid for because of this. :)
 
Re: GFCI on load side of AFCI?

If you use the test button on the GFCI, the AFCI should not trip. The use of a plug in GFCI tester may make the AFCI trip.
Don
 
Re: GFCI on load side of AFCI?

Don are you sure the built in test button on the GFI recpt. want trip the AFCI in the panel?

I just assumed it would because the built in test button connects the hot side of the load to the ground through a resistor, what would be the differents?

To be honest with you I have not tried the built in test button. I did have a GFI recpt. on a AFCI on a house rewire and when the inspector test the GFI he used a wiggy and touched one to the hot and one to the ground and in doing so it kicked the GFI recpt. and the AFCI in the panel.

Ronald :)
 
Re: GFCI on load side of AFCI?

Hi Ronald. When I do a residential final inspection, I always push the test button on the GFCI tester when I check bedroom receptacles. In the past few years, the only AFCI breakers that I have seen trip are Siemens, and they always trip. I would assume this is because the GFCI is required to trip at a lower current than the AFCI, but I'm not 100% on that.
 
Re: GFCI on load side of AFCI?

Thanks Ryan

That answers Dons comment on the built in test button.

I didn't consider the higher milliamps it takes to trip the GFCI section of the AFCI and Don could very well be correct.

Maybe some will and some want if I find out I'll let you no.

Thanks :)

[ February 12, 2004, 10:41 PM: Message edited by: ronaldrc ]
 
Re: GFCI on load side of AFCI?

Some of the first Siemens AFCI's on the market had a 5ma GFP in them and they were subject to nusent tripping. Siemens has since changed them to a 30ma GFP and they should not trip with the test button any more.
This brings up a kind of funny thing that our local inspector was doing when this change happened. he called me one day and said I don't think your AFCI's are any good. and I asked him what made him think that? and he told me that another electrician had told him that the little three light Ideal GFCI tester will trip a AFCI to know that the receptacle in question was in fact on the AFCI. But lately they haven't been tripping. I had to laugh at this one. When I told him that it wouldn't trip them anymore. He could't believe it. He said he won't red tag for that any more. I wounder how many AFCI's got changed because of this LOL
 
Re: GFCI on load side of AFCI?

Hello Wayne

I like that story about the inspector.Reminds of me I jump the gun a lot and say things that I shouldn't just because I don't have all the facts or a lot of times on line answer in error because I don't always bother to read enough of the thread.

I wonder why the AFCI manufacturers don't put it in the specs. that when used in conjunction with a GFI recpt. there might be problems? Of course this might hurt sales.

Thanks :)
 
Re: GFCI on load side of AFCI?

Ron,
The internal GFCI test button does not connect the hot to the grounding conductor via a resistor. If it did that then the test button would not work on GFCI that have been installed to replace two wire receptacles where there is no equipment grounding conductor at the receptacle location. The test button connects a resistor from the hot wire on the line side of the current coil to the grounded conductor on the load side of the coil. This creates the same inbalance through the current coil as a ground fault on the load side of the coil.
Don
 
Re: GFCI on load side of AFCI?

Hello Don


You're right The internal test button connects the load hot to the line neutral or grounded conductor through a resistor internally in the GFI recpt.I guess I should have said the grounded conductor or the neutral.But it still hooks it to the ground via the neutral. :)
 
Re: GFCI on load side of AFCI?

The wigger coil draws far more than 5ma and is quite capable of tripping an AFCI's GF aspect. By using the wigger on the outside GFCI receptical, you basically have a horse race to see who trips first.

Use the proper testers and this condition won't be happening.
 
Re: GFCI on load side of AFCI?

Boy thats a fast horse race both would probably kick with the wiggy before you have time to remove the wiggy probe from the terminal. :D

The hot load might hook in reverse as Don is saying I can't find my GFI diagram same differents either way.

But my point here is if you have a GFI fault it is going to be deceiving to a lot of people because both will more and likely trip.


Ron ;)

[ February 13, 2004, 12:14 PM: Message edited by: ronaldrc ]
 
Re: GFCI on load side of AFCI?

To expand on what Don has been saying, because the test button connects from hot on the line side to grounded conductor on the load side, it causes the receptacle being tested to see an imblance. However, because the current does get back to the grounded conductor rather than equipment ground, the upstream AFCI break will see no imbalance. Even if the AFCI breaker had a 5ma ground fault sensitivity, the test button on the gfci outlet shouldn't trip it. The test button on a plug in tester on the other hand diverts the current to the equipment ground, so it will cause the upstream AFCI to see the 5ma or so imbalance.
 
Re: GFCI on load side of AFCI?

Eprice
I never thought about it that way but your right on the money. we did have a problem with those first release AFCI's from Siemens. they would trip on Duo-Dehummers paddle fan controls and just switching a paddel fan off would trip them. But we haven't had any problems with them in a while. well except when the inspector thought they should trip with a GFCI tester. LOL :p
 
Re: GFCI on load side of AFCI?

Eprice

Sorry about the short answer this morning I didn't take enough time to study what you said. :)

You are right about the internal built in button not kicking the AFCI since the AFCI would just see it as an additional load across the neutral and hot.


Wayne what do you reckon was causing those Seimens AFCI to trip when you tested the old ones?
Where you using the built in tester or a external tester?


Thanks:Ronald :roll:
 
Re: GFCI on load side of AFCI?

Ron I was using the tester and the GFP in them was a 5ma type. After all the complaining they changed to a 30ma GFP and added som MOV's to prevent nusent tripping.
 
Re: GFCI on load side of AFCI?

Just for the heck of it I just set up the eq. circuit up on my electrical bench.

I used a GE single pole 20 amp.#THQL1120AFP AFCI and a 15 amp. recpt. 20 amp. feed through GFI receptacle # XGF15V-SP ShockSentry made by Cooper.


Didn't take any current readings but I used a Ideal solenoid wiggy tester and a test light with a 60 watt 120 volt incandescent light bulb.
Well heres what happen.

1.-With wiggy tested between the hot and neutral on AFCI 120 vac.

2.-With wiggy tested between the hot and neutral on GFI 120 vac.

3.-Pushed test button on AFCI, AFCI trips as should.

4.-Pushed built in test on GFI, GFI trips no effect on AFCI did not trip.

Now this fooled me like I said I didn't take any current measurements.

5.-Touched one wiggy probe to hot on GFI load side and the other one to the eq. ground on the GFI,GFI tripped had no effect on the AFCI held did not trip.

6.-Touched one wiggy probe to the hot load side of the AFCI breaker and the other wiggy probe to the eq. ground on the AFCI held did not trip the AFCI like I thought it would.The wiggy coils impedance is not low enough to allow enough current to flow to trip the AFCI breaker.

Now I used the light bulb tester for more current.

7.-Touched one probe of the bulb tester to the GFI hot load side and the other one to the GFI ground terminal, did this four times reseting the devices each time, First time just the AFCI kicked next three time both the AFCI breaker and the GFI recpt. tripped.It was a horse race.

I don't have a problem using them together now.
I think its a dependable combination.

Just thought I'd pass this information on might not help but sure can't hurt.

The only thing that has me puzzled now is like I said on one house inspection I had the electrical inspectors wiggy to kick my AFCI circuit when he went from the GFIs recpt. hot to ground.

His wiggy either pulled more current than my or it might have been since the run was longer than my bench circuit maybe the circuit capacitance made the difference?

Ronald :)
 
Re: GFCI on load side of AFCI?

Before I bought my SureTest I was tripping AF's GF aspect with a wigger...but then again that's probably a 40 year old Wigger handed down from my dad :D
 
Re: GFCI on load side of AFCI?

Tony like I said my wiggy would trip the GFI recpt. but not the AFCI.

I'm sure there quit a bit of deferents in the resistance of different solenoid tester coils.His was probably a lot lower.

Ronald :)
 
Re: GFCI on load side of AFCI?

Ron
You had to make me go out to my truck and get my wiggy LOL :p
wel I got both an older Square D and my Ideal Volt-Con. and I also brought in my Amp-probe to see just how much current they draw.
The Volt con was about 23 ma But the Square D was a whopping 578ma WoW :roll: Oh by the way, The Square D actuly say's WIGGY on it. must be there trade mark?
 
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