How to size Generator Conductors

[Marco Tacchini]

Goodmorning everybody, this is my first post Article 430.22 states that Motors in Continuous duty application need conductors sized not less then 125% of the Motor FLC. I could not find a similar statement for Generators (in Continuous Duty, of course). Does the same rule applies and, if yes, where is it written in the Code? Thks a Miliion, Marco Tacchini

 

[electricianexpress]

No, that rule does not apply. Basically size generator conductors as to the rating of the generator and over current protection. Generator being a supply and motor being a load would have totally different rules.

 

[iwire]

Dependent on the configuration of the generator 445.13 may apply.

445.13 Ampacity of Conductors. The ampacity of the
conductors from the generator terminals to the first distribution
device(s) containing overcurrent protection shall not
be less than 115 percent of the nameplate current rating of
the generator. It shall be permitted to size the neutral conductors
in accordance with 220.61. Conductors that must
carry ground-fault currents shall not be smaller than required
by 250.30(A). Neutral conductors of dc generators
that must carry ground-fault currents shall not be smaller
than the minimum required size of the largest conductor.

Exception: Where the design and operation of the generator
prevent overloading, the ampacity of the conductors
shall not be less than 100 percent of the nameplate current
rating of the generator.

 

[Smart $]

Dependent on the configuration of the generator 445.13 may apply.

And after the first OCPD(s), load and OCPD-determined ampacity rules apply... perhaps even the tap rules.