ashew
Member
- Location
- waterford michigan USA
Hi I need help on a question. Could you tell me where is it legal in the code to pull a larger feeder than necessary and size fuse based upon wire? Thank you in advanced.
pull larger feeder
- Thread starter ashew
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I don't think there is any code section which prohibits you from using a wire size larger than necessary... directly. The only occasions that I can think of are when permitted raceway fill would be exceeded.
In all the cases I can think of at present, being such a general application question, feeder OCPD can be sized for the wire ampacity.
In all the cases I can think of at present, being such a general application question, feeder OCPD can be sized for the wire ampacity.
Just thought of one scenario where OCPD may not be able to be sized for an over-sized feeder... and that would be when it is a service OCPD and cannot be rated any higher than the service rating. That would be the max no matter what ampacity feeder is installed on the load side.
mbrooke
Batteries Included
- Location
- United States
- Occupation
- Technician
Code is minimum not max. As long as the enclosure, pull box and conduit fill are not exceeded you can have the conductors as big as you want.
Common application is voltage drop or future expansion.
Common application is voltage drop or future expansion.
petersonra
Senior Member
- Location
- Northern illinois
- Occupation
- engineer
that would not be a feeder though. the OP asked about feeders.
I can't think of any cases where in general you are prohibited from upsizing both the feeder conductors and the OCPD accordingly.
It might affect what taps you can install on the feeder though.
- Location
- Chapel Hill, NC
- Occupation
- Retired Electrical Contractor
Just remember if you upsize the feeder then you have to upsize the equipment grounding conductor-250.122(B)
- Location
- New Jersey
- Occupation
- Journeyman Electrician
Since you said a feeder then there would be an OCPD on each end so the rating of the equipment at the end of the feeder wouldn't matter because that should be protected by the downstream OCPD. Do you have any more specific details about the installation?
- Location
- Massachusetts
Main lug panels could also be an issue to consider.
In those cases the feeder could not be protected higher than the panel rating regardless of the wire size.
In those cases the feeder could not be protected higher than the panel rating regardless of the wire size.
The conductors are on the load side of the service OCPD. That would make them feeders.
He asked a two-part question... and the second part is "size fuse based upon [feeder] wire size". The service OCPD is limited to the service conductor size, the feeder is not. Upsize the feeder but you cannot upsize the OCPD to match (unless you also upsize the service rating).
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