It is my understanding that AFCI breakers do not provide ground fault protection. If I install a GFCI receptacle on a circuit fed by AFCI breaker am I going to have any problems such as nuisance tripping etc...? I'm sure sales reps will say no but I'm wondering if anyone has actually done this. It is an outside outlet at the end of a long run to a bedroom and I was just trying for a little cost saving and to satisfy my curiosity.
GFCI on AFCI circuit
- Thread starter tomspark
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luke warmwater
Senior Member
Re: GFCI on AFCI circuit
It will work. AFCI's do have GFCI circutry but it is set at 30ma, much higher than 5ma for personal protection. This circutry helps the AFCI detect certain faults. Cutler Hammer has a AFCI/GFCI breaker.
It will work. AFCI's do have GFCI circutry but it is set at 30ma, much higher than 5ma for personal protection. This circutry helps the AFCI detect certain faults. Cutler Hammer has a AFCI/GFCI breaker.
bphgravity
Senior Member
- Location
- Florida
Re: GFCI on AFCI circuit
I agree with TODD, The GFCI receptacle should trip well before the AFCI breaker ever sees the ground-fault.
I agree with TODD, The GFCI receptacle should trip well before the AFCI breaker ever sees the ground-fault.
- Location
- Illinois
- Occupation
- retired electrician
Re: GFCI on AFCI circuit
I'm not sure about which will trip first. Of course, if the ground fault is less than the 30 to 50 mA required to trip the GFP in the AFCI, the GFCI should always trip without the AFCI tripping, but if the ground fault is greater than 50 mA, either or both devices could trip. In this case both would be seeing a ground fault above the trip level and which one trips will be based on the internal timing of the trip.
As far as the GFCI causing the AFCI to trip, this should not happen.
Don
I'm not sure about which will trip first. Of course, if the ground fault is less than the 30 to 50 mA required to trip the GFP in the AFCI, the GFCI should always trip without the AFCI tripping, but if the ground fault is greater than 50 mA, either or both devices could trip. In this case both would be seeing a ground fault above the trip level and which one trips will be based on the internal timing of the trip.
As far as the GFCI causing the AFCI to trip, this should not happen.
Don
jxofaltrds
Inspector Mike®
- Location
- Mike P. Columbus Ohio
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- ESI, PI, RBO
Re: GFCI on AFCI circuit
If this is a split feed you might. I'll have to try this.
If this is a split feed you might. I'll have to try this.
Re: GFCI on AFCI circuit
I have a situation like this that is causing problems. A GFCI was installed on an Arc Fault protected branch. Tripping the GFCI will cause the AFCI to open. The GFCI was tripped by the built in test button and a circuit test device. Both times the AFCI tripped. The branch was tested on a different AFCI with the same result. Testing the GFCI caused the AFCI to trip.
Anyone have any ideas???
I have a situation like this that is causing problems. A GFCI was installed on an Arc Fault protected branch. Tripping the GFCI will cause the AFCI to open. The GFCI was tripped by the built in test button and a circuit test device. Both times the AFCI tripped. The branch was tested on a different AFCI with the same result. Testing the GFCI caused the AFCI to trip.
Anyone have any ideas???
- Location
- Illinois
- Occupation
- retired electrician
Re: GFCI on AFCI circuit
Gent,
It appears that you have either a AFCI/GFCI combo, or that the GFP that is built into all AFCIs is set way lower than the specified 30 to 50 mA.
Don
Gent,
It appears that you have either a AFCI/GFCI combo, or that the GFP that is built into all AFCIs is set way lower than the specified 30 to 50 mA.
Don
- Location
- Illinois
- Occupation
- retired electrician
Re: GFCI on AFCI circuit
Roger,
There is no code requirement for an AFCI/GFCI combo at this time. I would expect that CH put it on the market in anticipation of additional requirements for AFCI use in the '05 code. Maybe bathroom or kitchen circuits?
Don
Roger,
There is no code requirement for an AFCI/GFCI combo at this time. I would expect that CH put it on the market in anticipation of additional requirements for AFCI use in the '05 code. Maybe bathroom or kitchen circuits?
Don
hurk27
Senior Member
- Location
- Portage, Indiana NEC: 2008
Re: GFCI on AFCI circuit
Don I have seen many ITE AFCI's trip with a GFCI tester and had an outside GFCI test button trip the AFCI. and when I use a GreenLee GFCI tester with the 5 settings the 7ma setting will trip the AFCI every time.
Don I have seen many ITE AFCI's trip with a GFCI tester and had an outside GFCI test button trip the AFCI. and when I use a GreenLee GFCI tester with the 5 settings the 7ma setting will trip the AFCI every time.
- Location
- Illinois
- Occupation
- retired electrician
Re: GFCI on AFCI circuit
hurk,
Everyting that I have read says that the GFP trip level in the AFCI is at least 30mA. The GFCI testers should only be putting a 8 mA ground fault on the circuit. The test button on the GFCI should not trip the AFCI as it does not create an actual ground fault.
Don
hurk,
Everyting that I have read says that the GFP trip level in the AFCI is at least 30mA. The GFCI testers should only be putting a 8 mA ground fault on the circuit. The test button on the GFCI should not trip the AFCI as it does not create an actual ground fault.
Don
hurk27
Senior Member
- Location
- Portage, Indiana NEC: 2008
Re: GFCI on AFCI circuit
This is what I'm told too but I've seen it with my own eyes. the newer AFCI's wont do it. maybe it was somthing with the first ones out on the matket?
This is what I'm told too but I've seen it with my own eyes. the newer AFCI's wont do it. maybe it was somthing with the first ones out on the matket?
luke warmwater
Senior Member
Re: GFCI on AFCI circuit
Roger, I just used one. We had a 'holiday package' wired in a large home. Receptacles were installed under all of the windows in the front of the house. On the second floor, there were outlets in the bedrooms and in the master bathroom that were on this circut, so we needed AFCI/GFCI protection. We could have used an AFCI breaker and GFCI receptacles, but with the cost of the new GFCI receptacles, I think that it was less expensive to use the combo breaker. Todd
Re: GFCI on AFCI circuit
[ April 23, 2003, 10:06 AM: Message edited by: gent ]
This is all new stuff. New construction, new AFCI and new GFCI receptacle. When the GFCI trips, it trips the AFCI. Both AFCI and GFCI receptacle were replaced but the situation stays the same. Testing another receptacle with a GFCI tester will not trip the AFCI, so it is not the applied ground fault tripping the AFCI.
[ April 23, 2003, 10:06 AM: Message edited by: gent ]
Re: GFCI on AFCI circuit
Todd,
The installer will have to be aware of what type AFCI can be used for the application.
I think Don is right that CH is getting a jump on things BUT, If in the future, whole house AFCI protection is required, the AFCI/GFCI will be necessary for very few applications and could be achieved with GFCI receptacles and downstream wiring at a lower cost.
Roger
[ April 23, 2003, 03:30 PM: Message edited by: roger ]
Todd,
this is the reason I asked the question. Your installation could have the smoke detectors on a GFI circuit which is in violation of NFPA 72.
The installer will have to be aware of what type AFCI can be used for the application.
I think Don is right that CH is getting a jump on things BUT, If in the future, whole house AFCI protection is required, the AFCI/GFCI will be necessary for very few applications and could be achieved with GFCI receptacles and downstream wiring at a lower cost.
Roger
[ April 23, 2003, 03:30 PM: Message edited by: roger ]
luke warmwater
Senior Member
Re: GFCI on AFCI circuit
Roger, the smokes are not on a the circut, so no problem. I'll agree that there is a limited use for the combination breaker right now. Todd
Roger, the smokes are not on a the circut, so no problem. I'll agree that there is a limited use for the combination breaker right now. Todd
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