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Do you de-rate feeder conductors in addition to de-rating a…

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Do you de-rate feeder conductors...
Do you de-rate feeder conductors in addition to de-rating a feeder conductor?
For example: If I have a 600 circuit breaker protecting a 600 amp feeder, do I derate the load alloowed on the feeder to 80% and then apply another de-rating to circuit breaker with non-continuous loads. That would make the load available of 600 x .8 x .8 = 384 amps.
Submitted: 2 years ago.Category: Electrical
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Answered in 31 minutes by:
2/15/2016
Electrician: Mike G., Master Electrician replied 2 years ago
Mike G.
Mike G., Master Electrician
Category: Electrical
Satisfied Customers: 8,419
Experience: Proven Professional 49 years Experience
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Hi, I'm Mike G and I'll be assisting you. You only derate the wire and then size the breaker to the number. The size of the breaker can be increased if the calculation shows more than the size of a listed breaker, step up to next size.

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