Breaker lugs too small for wire?

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AV ELECTRIC

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By saying "at least for this code cycle" you imply that you believe the option is something that should be removed for future codes. Why do you feel this way? It's a perfectly safe, compliant installation.

Pigtailig to lights and recepticals with smaller wire is fine but splicing at the source doesnt seem like the best way to go I understand in situations there may not be an alternative are stab in recepticals compliant yes have they limit there use over the years buy eliminating #12 for this application ? Ide prefer ordering a breaker with larger lugs Will they or should they look at this in the future maybe only time will tell
 

George Stolz

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I don't see a parallel between backstabbed receptacles and pigtailing an upsized feeder at all. One has a questionable termination method, the other does not.
 

ptrip

Senior Member
...but splicing at the source doesn't seem like the best way to go ...

I guess I'm confused. The amount of power available at the source and the amount of power at the end are the same (essentially). Why would splicing at the beginning be worse than splicing at the end?

Truth be told ... when performing arc flash calculations at a prior job I found that the arc flash hazards were much greater the further away from the breaker you were. This was due to the time lag of the arc incident and the breaker shutting down. Theoretically, this means that the closer the splice (weak point) is to the protective device the better.

Thoughts?
 

iwire

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Pigtailig to lights and recepticals with smaller wire is fine but splicing at the source doesnt seem like the best way to go I understand in situations there may not be an alternative are stab in recepticals compliant yes have they limit there use over the years buy eliminating #12 for this application ? Ide prefer ordering a breaker with larger lugs Will they or should they look at this in the future maybe only time will tell


Picture this, we do a lot of large buildings, on one large warehouse the prints called for 4 AWG copper to supply the roof top 20 amp 125 volt service receptacles.

How would you connect a 4 AWG to a standard 20 amp 125 volt breaker?
 

AV ELECTRIC

Senior Member
I don't see a parallel between backstabbed receptacles and pigtailing an upsized feeder at all. One has a questionable termination method, the other does not.

Its just a comment on how the code evolves over the years as we find out new information on material and installation and its relation to safety
 

AV ELECTRIC

Senior Member
I guess I'm confused. The amount of power available at the source and the amount of power at the end are the same (essentially). Why would splicing at the beginning be worse than splicing at the end?

Truth be told ... when performing arc flash calculations at a prior job I found that the arc flash hazards were much greater the further away from the breaker you were. This was due to the time lag of the arc incident and the breaker shutting down. Theoretically, this means that the closer the splice (weak point) is to the protective device the better.

Thoughts?

The consensus says you are correct. Is this a big deal as pertaining to voltage drop ? probably not . I prefer to limit splices as much as i can especially with higher loads.
 

AV ELECTRIC

Senior Member
Picture this, we do a lot of large buildings, on one large warehouse the prints called for 4 AWG copper to supply the roof top 20 amp 125 volt service receptacles.

How would you connect a 4 AWG to a standard 20 amp 125 volt breaker?

Can you special order a breaker with a larger lug ? ive done it for larger breakers ime not sure if you can for smaller yes there are limitations on what we can do with the material that is available and time frame
 

iwire

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Can you special order a breaker with a larger lug ? ive done it for larger breakers ime not sure if you can for smaller yes there are limitations on what we can do with the material that is available and time frame

These are standard one inch single pole breakers, you would not get them with a lug for 4 AWG.

But again why? There is no quality, functionality, code reason, or safety issue with splicing on some 10 AWG to the 4 AWG which is what we did at the panel end.
 

roger

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Fl
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When mixing conductors in long runs for VD I have always liked putting the larger conductors somewhere in the middle and ends of the run just for confussion purposes. :grin:


Roger
 

mivey

Senior Member
When mixing conductors in long runs for VD I have always liked putting the larger conductors somewhere in the middle and ends of the run just for confussion purposes. :grin:


Roger
If there's anything I hate, it's being confussed.
 
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