# VFD and GFCI outlet



## nelsonchenknives (Aug 18, 2018)

hi, 

i'm new here and this is my first post, apologies in advance for any mistakes. 

here's my question, i have a KMG belt grinder that i want to convert to variable speed and direct drive. i know that VFD does not work on GFCI outlets, but GFCI is all i have in my garage shop. the obvious solution that i can think of is to replace the outlet with a non-GFCI one, although it would certainly violate safety codes. 

so, how do others deal with this conflict? or is there something else i'm missing here?


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## OneStaple (Aug 19, 2018)

I'll caveat this all by saying that you should check your local code to know what is actually allowed. Things vary by region. And if you're not skilled in electric work, consult/hire an electrician.

I don't believe I've needed to run a VFD off a GFCI'ed outlet, so I don't know if it's actually a problem.

I believe 240V outlets do not require GFCI, and using them will allow for VFDs that can handle larger motors. Usually 120V single-phase input VFDs go up to about 1.5HP, I think. 240V usually can do VFDs up to 3HP. Of course, putting in a 240V line/outlet is more complicated than swapping one of your 120V outlets to non-GFCI, but the 240V line *should* (see note at beginning) be to code.

There are often items in the code that say the outlet can be non-GFCI if it is a dedicated outlet to only one item (appliance?), such as a fridge. Not sure how you'd "prove" this, and I think it's an unlikely path forward, but thought I'd mention it.

For myself in my own garage, I would put in or use a 240V outlet with the appropriate VFD or I'd swap a 120V line to non-GFCI without hesitation. But that's just me, and I'm comfortable doing my own electrical work.

Tyler


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## parbaked (Aug 19, 2018)

Yes...put a 240V outlet if that bypasses the GFCI requirement or just install a non-GFCI outlet just for the VFD>


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## Bensbites (Aug 19, 2018)

I did a quick google search. Sounds like some GFI outlets can handle VFF, others can’t. 

https://www.schneider-electric.us/en/faqs/FA274920/


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## parbaked (Aug 19, 2018)

If you actually read the link you posted, it recommends not to use their product and instead refers you to another company (Bender Inc) whose VFD compatible outlet costs $700!


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## Bensbites (Aug 19, 2018)

parbaked said:


> If you actually read the link you posted, it recommends not to use their product and instead refers you to another company (Bender Inc) whose VFD compatible outlet costs $700!



Thanks for the snark. I did read the link and passed on relevant information in it including the source of the information. This is as much of an answer as anyone else has given.


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## nelsonchenknives (Aug 20, 2018)

thanks for all the input. i do own the house so it is very tempting to just swap out the outlets, since it's the cheaper solution. i do like the idea of putting in 240v though, since it'll allow me to run bigger machines, and also potentially solving my VFD/GFCI problem.


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