AFCI
- Thread starter ronaldrc
- Start date
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hurk27
Senior Member
- Location
- Portage, Indiana NEC: 2008
Re: AFCI
Ron I haven't. but I could think of a few things that probley could. I think if there is a device or a apliance that would produce a spike or surge in the neutrals the the afci might trip. because it does incorperate a GFCI. the same thing did happen to them(gfci's), like a paddle fan with a 4 position fan control(dew'o dehummer) arcing inbetween the slections would trip any gfci close by on the same circuit. but the all the problems with AFCI's I have to date involves load side, and mainly involve the neutral to ground fault or neutral connected to wrong neutral down stream. which would cause problems with a gfci too
Ron I haven't. but I could think of a few things that probley could. I think if there is a device or a apliance that would produce a spike or surge in the neutrals the the afci might trip. because it does incorperate a GFCI. the same thing did happen to them(gfci's), like a paddle fan with a 4 position fan control(dew'o dehummer) arcing inbetween the slections would trip any gfci close by on the same circuit. but the all the problems with AFCI's I have to date involves load side, and mainly involve the neutral to ground fault or neutral connected to wrong neutral down stream. which would cause problems with a gfci too
curt swartz
Electrical Contractor - San Jose, CA
- Location
- San Jose, CA
- Occupation
- Electrical Contractor
Re: AFCI
Most AFCI's do NOT include GFCI protection. I know Cutler-Hammer does make a combination AFCI/GFCI unit but standard AFCI breakers include ground fault protection that is set at a much higher level than a GFCI and not designed to protect against electrical shocks. I'm not sure what the trip level is set at but I believe it is in the 30-50ma range.
Most AFCI's do NOT include GFCI protection. I know Cutler-Hammer does make a combination AFCI/GFCI unit but standard AFCI breakers include ground fault protection that is set at a much higher level than a GFCI and not designed to protect against electrical shocks. I'm not sure what the trip level is set at but I believe it is in the 30-50ma range.
Re: AFCI
I've not been having problems ,I'm still wondering how much isolation there is between the line and load.
In other words if the arc faults on the line side are of high enough amplitude will they kick the AFCI even if they are not on the load side of the AFCI.
Ronald
I've not been having problems ,I'm still wondering how much isolation there is between the line and load.
In other words if the arc faults on the line side are of high enough amplitude will they kick the AFCI even if they are not on the load side of the AFCI.
Ronald
Re: AFCI
I know most on here wonder why I ask this question.
I do a lot of troubleshooting work. I once went on a service call where all the recptacles in one office where dead.
The maintenance personnel had already spent several hours trying to find the problem.
When I got there the first thing I did was to check the hot to the equipment ground to see if we might have a broken neutral. We not only had a broken neutral the rest of my checks indicated all conductors where broken or open from the panel to the recptacles.
I ask if someone might have cut it doing construction work they said no.
After tearing out walls and spending another couple hours tracing the route of the circuit we found a GFIC recptacle in behind a bookcase where there use to be a small kitchenett.The electricians had feed this GFIC recptacle first and put the rest of the office recptacles on the load side.So when it kicked it disconnected all conductor on the load side which fed the recptacles in this office.We put the recptacles on the line side of the GFIC recptacle and the problem was fixed took about five minutes after spending about a day of finding it.
Now my to the AFCI if it is possible for a arc fault to kick the AFCI from a arc fault on the line side I think this should be pointed out in the litature or instructions and sent with the AFCI. So when electricians go on troubleshooting calls if after several hours of checking the load of this AFCI circuit.They are not left standing there scratching their heads.
Ronald
I know most on here wonder why I ask this question.
I do a lot of troubleshooting work. I once went on a service call where all the recptacles in one office where dead.
The maintenance personnel had already spent several hours trying to find the problem.
When I got there the first thing I did was to check the hot to the equipment ground to see if we might have a broken neutral. We not only had a broken neutral the rest of my checks indicated all conductors where broken or open from the panel to the recptacles.
I ask if someone might have cut it doing construction work they said no.
After tearing out walls and spending another couple hours tracing the route of the circuit we found a GFIC recptacle in behind a bookcase where there use to be a small kitchenett.The electricians had feed this GFIC recptacle first and put the rest of the office recptacles on the load side.So when it kicked it disconnected all conductor on the load side which fed the recptacles in this office.We put the recptacles on the line side of the GFIC recptacle and the problem was fixed took about five minutes after spending about a day of finding it.
Now my to the AFCI if it is possible for a arc fault to kick the AFCI from a arc fault on the line side I think this should be pointed out in the litature or instructions and sent with the AFCI. So when electricians go on troubleshooting calls if after several hours of checking the load of this AFCI circuit.They are not left standing there scratching their heads.
Ronald
al hildenbrand
Senior Member
- Location
- Minnesota
- Occupation
- Electrical Contractor, Electrical Consultant, Electrical Engineer
Re: AFCI
Ronald,
I think you've raised an interesting question. The complete answer will require the manufacturers of AFCIs to tell us more than they currently have. To my knowledge, none of them are saying how their AFCIs actually work. Sure they'll tell us about the UL1699 tests that are passed, but so far, I haven't heard a word about the actual circuitry of the "black box" inside the breaker.
Here's my take, from what I have gleaned over this last half year.
The 15 or 20 amp 125 volt AFCI has to "see" current events exceeding a threshold level of 50 to 70 amps at least twice in an eight half cycle period. To me, this means the primary sensor is a current sensor. If so, the device will respond to downstream events only, because current changes upstream from the AFCI simply can't be sensed.
The GFP portion of the AFCI circuitry will also only see the downstream changes in current (just like a class A GFCI).
Does anyone else have any knowledge to contribute about the circuitry in these things?
Al
Ronald,
I think you've raised an interesting question. The complete answer will require the manufacturers of AFCIs to tell us more than they currently have. To my knowledge, none of them are saying how their AFCIs actually work. Sure they'll tell us about the UL1699 tests that are passed, but so far, I haven't heard a word about the actual circuitry of the "black box" inside the breaker.
Here's my take, from what I have gleaned over this last half year.
The 15 or 20 amp 125 volt AFCI has to "see" current events exceeding a threshold level of 50 to 70 amps at least twice in an eight half cycle period. To me, this means the primary sensor is a current sensor. If so, the device will respond to downstream events only, because current changes upstream from the AFCI simply can't be sensed.
The GFP portion of the AFCI circuitry will also only see the downstream changes in current (just like a class A GFCI).
Does anyone else have any knowledge to contribute about the circuitry in these things?
Al
Re: AFCI
Al thanks for the response.
I think even if the breaker did kick from line side arc faults that would be a plus but we should know this to make our job easier.
And by upstream you mean line side I think?
And downstream would be load is this correct?
Ronald :roll:
Al thanks for the response.
I think even if the breaker did kick from line side arc faults that would be a plus but we should know this to make our job easier.
And by upstream you mean line side I think?
And downstream would be load is this correct?
Ronald :roll:
al hildenbrand
Senior Member
- Location
- Minnesota
- Occupation
- Electrical Contractor, Electrical Consultant, Electrical Engineer
Re: AFCI
Yes,
Downstream = load
Upstream = line
Apologies for the confusion.
Yes,
Downstream = load
Upstream = line
Apologies for the confusion.
al hildenbrand
Senior Member
- Location
- Minnesota
- Occupation
- Electrical Contractor, Electrical Consultant, Electrical Engineer
Re: AFCI
Cool!
Five stars. Thanks to whoever took the moment.
Al
Cool!
Five stars. Thanks to whoever took the moment.
Al
hurk27
Senior Member
- Location
- Portage, Indiana NEC: 2008
Re: AFCI
Al what I was thinking was back when we use to have the master bath on with the master bedroom or had a paddle fan located in the master bath, when receptacle gfci devices just came out. the fan controls like the duo dehummer had 4 speed positions on them when you switched between the speeds it would produce a voltage spike into the circuit. as this was on the line side of the gfci it would be enough to trip the gfci maybe because of the timing of the spike on the rise. and the way I solved this problem was to put a MOV across the gfci. but I was wondering since the gfp in a afci is at a higher rate then it might not be enough to trip it. but what if a larger spike were to come down the line ? this I dont know unless some testing were to be conducted.
Al what I was thinking was back when we use to have the master bath on with the master bedroom or had a paddle fan located in the master bath, when receptacle gfci devices just came out. the fan controls like the duo dehummer had 4 speed positions on them when you switched between the speeds it would produce a voltage spike into the circuit. as this was on the line side of the gfci it would be enough to trip the gfci maybe because of the timing of the spike on the rise. and the way I solved this problem was to put a MOV across the gfci. but I was wondering since the gfp in a afci is at a higher rate then it might not be enough to trip it. but what if a larger spike were to come down the line ? this I dont know unless some testing were to be conducted.
al hildenbrand
Senior Member
- Location
- Minnesota
- Occupation
- Electrical Contractor, Electrical Consultant, Electrical Engineer
Re: AFCI
I think we've got a lot to learn about the insides of these "black boxes".
I think we've got a lot to learn about the insides of these "black boxes".
Re: AFCI
My thoughts on the AFCI have nothing to do with the GFI feature they are because the microprocessor inside recognizes the signature of an arc.And if the arc where of high enough amplitude on the line side would it pick up on it?
Have these test been run or are they just selling as is?
Ronald
My thoughts on the AFCI have nothing to do with the GFI feature they are because the microprocessor inside recognizes the signature of an arc.And if the arc where of high enough amplitude on the line side would it pick up on it?
Have these test been run or are they just selling as is?
Ronald
luke warmwater
Senior Member
- Location
- Bremerton, Washington
Re: AFCI
Curt an important point on AFCI. While most do not contain a Class A GFCI, all do contain a GFP trip circuit, set at 30 to 50 mA. This device helps the AFCI detect some of the arcing faults, and will also trip on a neutral to ground connection.
Curt an important point on AFCI. While most do not contain a Class A GFCI, all do contain a GFP trip circuit, set at 30 to 50 mA. This device helps the AFCI detect some of the arcing faults, and will also trip on a neutral to ground connection.
georgev@bellevue.net
Member
- Location
- Iowa
Re: AFCI
One thing I have noticed , is in the beginning of the Arc Faults , there was a problem with the Cutler Hammer AFCI's in the Omaha area due to the test button sticking. They have assured me it is taken care of.
One thing I have noticed , is in the beginning of the Arc Faults , there was a problem with the Cutler Hammer AFCI's in the Omaha area due to the test button sticking. They have assured me it is taken care of.
dpl1
New member
- Location
- North Carolina
Re: AFCI
I have had a lot of trouble with AFCI's. I have one house that I have turned on temp power and I can't keep the ASCI breaker set in one bedroom if you apply any kind osf load. Got an suggestions?Originally posted by ronaldrc:
I know that AFCI have not been out long.
But has anyone had any nuisance kicking from faults on the line side or circuits not fed with the AFCI causing the AFCI to kick?
Ronald
- Location
- Illinois
- Occupation
- retired electrician
Re: AFCI
dpl,
The most likely problem is a grounded to grounding conductor short some where in the circuit. All AFCIs have a ground fault protection system built in. This GFP circuit trips at 30 to 50 mA of ground fault current, but does not provide GFCI protection for people.
Don
dpl,
The most likely problem is a grounded to grounding conductor short some where in the circuit. All AFCIs have a ground fault protection system built in. This GFP circuit trips at 30 to 50 mA of ground fault current, but does not provide GFCI protection for people.
Don
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