AFCI/GFCI protection via main breaker?

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henryf

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Just saw a video from France showing how they provide each row of breakers on their DIN rail panel with AFCI/GFCI protection via the first breaker on the row. IE, a 63A breaker provides AFCI/GFCI protection for the 5 16A breakers on the row.

Has anyone tried this here? Seems like it could save a lot on breakers and eliminate failure points if done right.
 
There are no AFCIs rated more than 20 amps in the US as that is the maximum circuit size that the code requires AFCI protection for.
The code does permit a feeder or main breaker to provide the required GFCI protection. See 215,9
 
don_resqcapt19 said:
There are no AFCIs rated more than 20 amps in the US as that is the maximum circuit size that the code requires AFCI protection for.
The code does permit a feeder or main breaker to provide the required GFCI protection. See 215,9
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Thanks, was thinking AFCI was available in same amperages as GFCI.
 
henryf said:
Here’s the linkto the video
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Thanks. Seen that guy before, interesting channel.

So it's 30ma GFI (as we'd call it) protection for each group of a half dozen circuits. Whereas in the US we have 5ma GFCI protection on a single 15-20A circuit.

No indication there's any arc-fault stuff going on.

No one could really try that here, as we just do things so differently.
 
don_resqcapt19 said:
There are no AFCIs rated more than 20 amps in the US as that is the maximum circuit size that the code requires AFCI protection for.
The code does permit a feeder or main breaker to provide the required GFCI protection. See 215,9
Click to expand...
Don, sorry but you have this reversed. A GFCI on a feeder CAN be used to satisfy 210.8. Now whether this is a good idea is a whole other conversation. In most cases I think it is a terrible practice for obvious reasons.
 
texie said:
Don, sorry but you have this reversed. A GFCI on a feeder CAN be used to satisfy 210.8. Now whether this is a good idea is a whole other conversation. In most cases I think it is a terrible practice for obvious reasons.
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That is what I thought I said. :)
 
henryf said:
Just saw a video from France showing how they provide each row of breakers on their DIN rail panel with AFCI/GFCI protection via the first breaker on the row. IE, a 63A breaker provides AFCI/GFCI protection for the 5 16A breakers on the row.

Has anyone tried this here? Seems like it could save a lot on breakers and eliminate failure points if done right.
Click to expand...
Somebody asked during a continuing education class if they could just install a two pole GFCI breaker to provide protection for a house. Said it could pass in some locations but due to leakage can only imagine how many times a day you would have to reset a whole house 5 milliamps trip main breaker. Don't even know if anybody makes a single or two pole GFCI circuit breaker for residential panels over 60 amps. I know that you cannot use type THHN/THWN wire on ER rooms that are on LIM panels because even that top quality insulation produces too much leakage to ground. To me the insulation on type NM-B appears to be to very similar to THHN wire. Never read how much leakage a thousand foot of type NM-B cable might have.
 
garbo said:
Somebody asked during a continuing education class if they could just install a two pole GFCI breaker to provide protection for a house. Said it could pass in some locations but due to leakage can only imagine how many times a day you would have to reset a whole house 5 milliamps trip main breaker. Don't even know if anybody makes a single or two pole GFCI circuit breaker for residential panels over 60 amps. I know that you cannot use type THHN/THWN wire on ER rooms that are on LIM panels because even that top quality insulation produces too much leakage to ground. To me the insulation on type NM-B appears to be to very similar to THHN wire. Never read how much leakage a thousand foot of type NM-B cable might have.
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Insulation alone isn't necessarily the problem. Leakage due to capacitive effects is what generally is an issue. The longer the run the more "capacitor" you end up having.
 
Doesn't France use 50Hz 230v ? Not sure how that will effect things.
 
This is why I don't like European electrical installations. Some arcing that probably would have been contained within our panels quickly consumed the plastic "consumer unit", spread outside and caused major damage to the structure.

We build things like a Sherman Tank for a reason!


-Hal
 
kwired said:
Insulation alone isn't necessarily the problem. Leakage due to capacitive effects is what generally is an issue. The longer the run the more "capacitor" you end up having.
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When I replaced my first LIM feed HR receptacle asked the sparky why they did not use type THHN/THWN wire and he told me due to leakage which didn't make sense but capacitive effects would be the proper term. Thanks. And yes you can teach on old retired dog new things.
 
acrwc10 said:
Doesn't France use 50Hz 230v ? Not sure how that will effect things.
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Is 240 volts to ground instead of 120. Will sustain an arc better than 120 does making it easier to detect true arcing faults that are problematic in nature and having less undesired trips like we have on 120 volts here in North America because we can't tell as easily what is a problematic arc and what isn't.
 
garbo said:
When I replaced my first LIM feed HR receptacle asked the sparky why they did not use type THHN/THWN wire and he told me due to leakage which didn't make sense but capacitive effects would be the proper term. Thanks. And yes you can teach on old retired dog new things.
Click to expand...
I guess different insulation types will have different capacitive effects.
 
kwired said:
I guess different insulation types will have different capacitive effects.
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Different materials will have Different 'dielectric constants', but most building wire insulation has similar properties. If I had to guess, I'd bet the factor here is insulation _thickness_. The thicker the insulation the lower the capacitance.

Jon
 
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