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Tandem 500hp VFD

Tandem 500hp VFD

Tandem 500hp VFD

(OP)
just getting involved in a project with two 500hp 480volt motors coupled together on a common belt driven shaft for a dredge pump. I will have a step down transformer 4,160 to 480, question is, is there any way of not having a main along with branch breakers for each drive?

RE: Tandem 500hp VFD

Maybe.  If the installation meets the requirements of Note 3 to Table 450.3(A) in the NEC and if the secondary conductors can be installed per one of the rules in 240.21(C), you are not required to have a main.

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