Part X Adjustable speed drive Overcurrent Protection

[Rickyghart]

I am trying to nail down the code section that would size the OCPD that will apply to a VFD input rating of 233A, intermitent duty. 430-122 says 125% for conductor ampacity to the drive. 430-128 says 115% for disconnecting means but that is not what I need to size overcurrent, I'm thinking.

What I am thinking is since a VFD is an electronic device, not a motor, nothing in Article 430 applies on the input for the drive. I can set the OCPD at 125% and let the drive do what it needs to do to start the motor on the output.

What am I missing?

 

[petersonra]

most drives these days come with instructions that allow up to 250% OCPD based on the rated input current, just like any other motor circuit.

 

[Rickyghart]

most drives these days come with instructions that allow up to 250% OCPD based on the rated input current, just like any other motor circuit.

Looking at the minimum size requirement.....and I know.... the minimum fuse is a 5A.
so no NEC requirrement just manufacture recomendations