Machine Wiring

[A/A Fuel GTX]

I have a processing machine with numerous motors and electronics as part of the assembly. This particular machine has a FLA rating of 60A @ 208V, 3 Phase. Would I use 430.52 to size the OCPD and 430 Part II for sizing the conductors?

 

[augie47]

IMO, the wording of Art 409 could be improved in this regard, but, as I read it, all the adjusting should have been done prior to affixing the require nameplate and you are only required to meet the listed ampacity requirement, in your case, 60 amps.

 

[mbeatty]

IMO, the wording of Art 409 could be improved in this regard, but, as I read it, all the adjusting should have been done prior to affixing the require nameplate and you are only required to meet the listed ampacity requirement, in your case, 60 amps.

This is also my belief.

 

[pfalcon]

Speculating,
It appears to me that for a standard industrial plant:

We buy a machine tool with a single point fused disconnect on the electrical panel. 409.21 applies to that disconnect and the conductors below the disconnect.

If we were to buy a machine tool such that we were running to branch circuits (which we don't) then 409.21 applies to the buss head fused disconnect and the conductors running to the machine.

Or am I in the weeds?

 

[justdavemamm]

I'm a electrical (controls & instrumentation) design engineer of "processing machine" and the like.That's how I expect the supply, as stated on the panel nameplate that's on the machine and the prints I furnish.

In most cases I've already rounded up a tad to account for future additions & changes.

I've also seen engineers simply use the disconnect rating (30,60,100, ...) amperage for specifying the supply. I get suspicious when I see a nice round even number.