5HP 120V DC Motor Circuit

[tryinghard]

If I have a 5HP 120V DC continuous duty motor wouldn?t the circuit be as follows?

1) Controller with Overloads (sized from the nameplate, 45A = 35A x 125%, as per 430-32)

2) OCPD (located near motor and controller as TD fuses and disconnect, 70A = 40A x 175% as per 430-6, 52, & 102), 2 cu #6?s 1 #8 from OCPD to OL & Motor as per 430-22, 310-16 & 250-122.

3) Source (inverse time circuit breaker 180? to OC TD fused disconnect, 100A = 40A x 250% as per 430-52) also 51,600 CM = 2x12.9x40Ax180?/3.6V requires 2 #3?s & 1 #8 as per 310-16 & 250-122.

Is this correct?

 

[davidr43229]

Everything looks ok,
What is your question?

 

[tryinghard]

Thanks I?m looking for opinions/verifications for correctness, to make sure I?m not missing something obvious.

 

[iwire]

1) Controller with Overloads (sized from the nameplate, 45A = 35A x 125%, as per 430-32)

Ah I don't have a book handy but I don't recall every adding 125% to the nameplate data of a motor to size the OLs.

 

[tryinghard]

It?s the one time to use the nameplate amperes rather than the tables in 430-XIII, see 430-32(A)(1) & 430-6(A)(1)-(2)

 

[Psychojohn]

Out of curiosity, what is supplying the DC.

We usualy calculate OL size to the motor SF and ambient temp. of the OL location.