Time Delay Fuses

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sparkyboys

Senior Member
Location
Columbus, ga
When calculating for time delay fuses at 175% of the FLC and the fuses do not hold the starting current and then increasing to 225% for FLC--Would a different size wire need to be calculated for the motor or just a different class and size time delay fuse?
 
I agree with Gus.

The wires only need to sized to carry the tabulated running load amps from the Tables in 430. You would not need to upsize the branch circuit conductors if you took advantage of Exception #2(b) to 430.52(C)(1).

Chris
 
When calculating for time delay fuses at 175% of the FLC and the fuses do not hold the starting current and then increasing to 225% for FLC--Would a different size wire need to be calculated for the motor or just a different class and size time delay fuse?

You need to select the proper class fuse for your motor charecteristics.
 
Hey, thanks everyone.

Two more questions:

1. Is a fusible motor controller disconnect the same as a variable speed drive?

If not...

2. Which comes first before the motor?
 
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