Portable generator conductor rating

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Struggling to understand 445.13..

445.13 Ampacity of Conductors. The ampacity of the conductors
from the generator to distribution devices containing overcurrent
protection must not be less than 115 percent of the nameplate
current rating of the generator


So, a portable generator rated for 7,500 running watts can sustain a 31.25A draw.
The customer currently has a 5,500 running watts genny, but they can possibly get a bigger one down the line.
Does that mean that we'll be running 8/3 between the L14-30R and the service panel, even though the 14-30R is rated for 30A, just because many gennys out there that use L14-30 are capable of sustaining a higher current?
 

iceworm

Curmudgeon still using printed IEEE Color Books
Location
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Occupation
EE (Field - as little design as possible)
Struggling to understand 445.13..

445.13 Ampacity of Conductors. The ampacity of the conductors
from the generator to distribution devices containing overcurrent
protection must not be less than 115 percent of the nameplate
current rating of the generator

445.13 only applies to the conductors fron the alternator terminals to the first OCP. The portable generators you are describing will have a cb on the gen frame.

I don't do much with residential grade portable gens, but I would think the gen CB feeding the L14-30 receptacle is 30A - size of the gen shouldn't matter.

ice
 
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ceb58

Senior Member
Location
Raeford, NC
445.13 only applies to the conductors fron the alternator terminals to the first OCP. The portable generators you are describing will have a cb on the gen frame.

I don't do much with residential grade portable gens, but I would think the gen CB feeding the L14-30 receptacle is 30A - size of the gen shouldn't matter.

ice

Agreed, if the generator has OCD built into it then 445.13 doesn't apply.
 

goldstar

Senior Member
Location
New Jersey
Occupation
Electrical Contractor
445.13 only applies to the conductors fron the alternator terminals to the first OCP. The portable generators you are describing will have a cb on the gen frame.

I don't do much with residential grade portable gens, but I would think the gen CB feeding the L14-30 receptacle is 30A - size of the gen shouldn't matter.

ice
I agree. The CB on the generator takes the ampacity into consideration. In addition you probably can't buy a 30 amp power cord made with # 8 wire unless you make up your own.
 
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