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VFD: In MCC Or Separate Cabinet?

VFD: In MCC Or Separate Cabinet?

VFD: In MCC Or Separate Cabinet?

Good day, all....

Looking for some practical advice on whether to integrate a 200 HP PowerFlex 755 VFD as part of a new Allen Bradley Intellicenter, or keep the VFD in it's own cabinet separate from the MCC. I know both can be done, but I'm looking for practical advice either way.



Galatians 2:20

RE: VFD: In MCC Or Separate Cabinet?

My vote is for a separate cabinet. If/when the VFD must be replaced, a separate cabinet could allow flexibility to replace with a different brand or model if need be.

RE: VFD: In MCC Or Separate Cabinet?

If you put it in a separate cabinet, you then have to put a Feeder CB in the MCC, run conduit to feed the VFD cabinet, then have another local disconnect in the VFD cabinet in order to be NFPA 70E compliant. Way more work for no real benefit in my opinion. At 200HP the space in the MCC for the drive will just have a wall mount drive anyway. there are no bus stabs or anything that makes it special. So replacing it is no different than just replacing a wall mount drive. then because it's an IntelliCenter and you likely have a Rockwell PLC, you can have the PLC automatically reprogram the replacement drive for you, so all you need to do it 3 wires in / 3 wires out and plug in the Ethernet cable.

If you are going the IntelliCenter route, replacing it with a different brand of drive is kind of an about face on the entire concept anyway.

" We are all here on earth to help others; what on earth the others are here for I don't know." -- W. H. Auden

RE: VFD: In MCC Or Separate Cabinet?

I defer to the preceding advice. Looks like my opinion was from ill-informed perspective.

RE: VFD: In MCC Or Separate Cabinet?

I would say 110kW (147HP) VSD is the limit for mounting in an MCC.

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