I am having electrical work done to have a 240V outlet installed for my Redline, 80mm, 240V spindle. However, my local code requires GFCI protection for all circuits located on a garage, does anyone have a recommendation on how to deal with this requirement without constantly tripping the breaker?
Also not an electrician but can’t you install a non GFCI as the first outlet in the circuit and just use that? GFCI only protects the downstream circuits no?
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You might contact your local inspector to see if there are any localized exemptions.
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Yeah, I actually just thought of that too. I’m hoping I get lucky and can get an exception for it.
Otherwise I’m hoping I get lucky and someone else in the forum has already found a way to mitigate the noise from the VFD to not trigger the GFCI
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I have no idea, but the electrician I talked to didn’t bring that up as an option so I’m guessing that may not work as expected.
When I faced this problem 10 years ago, the inspector said the Code allowed something called a “special use circuit” without GFCI protection.
It must have only one receptacle on the circuit. Something like this:
and the receptacle had to be labeled NON-GFCI.
I don’t know if this is still an option within the National Electrical Code or if it’s been removed. Your inspector should know.
Mike
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There are 50 answers but if it is going to be inspected you can bet the inspector will take the path that covers him, not you. The easiest answer is to ensure the electrician installs GFCI breakers for the garage ckts in the panel and not GFCI outlets or a single point GFCI protection in a sub panel. Get it inspected smile and thank the nice inspector, don’t say much. After he leaves spend $20 at home depot and swap the GFCI breaker feeding the VFD for a non-GFCI breaker. Takes about 10minutes. If you are not a power guy at all, turn off the main breaker to remove power from most of the panel and have spouse hold the flashlight while you swap breaker, or find a power savvy buddy to do it. GFCI breakers for the control panel, laser, water pump, dust collector,etc. will be fine and are good idea. With that said, make certain everything is properly grounded and tied together for safety reasons. I have done this more time than I can count for GFCI and AFCI breakers. My dyson vacuum trips AFCI breakers as does a treadmill. Just my opinion, I am an engineer, not an electrician, but been there done that.
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My spindle is on a GFCI breaker, and it has never tripped for me.
ARC Fault breakers might give you trouble though.gfci shouldnt
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@BKurk tearing it up with our electrical questions this week!
The exception is. You may supply machine with type of power it requires. The 220v devices that require GFCI protection are Hot Tubs and Swimming Pools.
Your electrician may be strocking you because it would be VERY expensive,
Work around.
Have them put in a 12/3 home run and only wire it for a 110v standard outlet then change the outlet and bracker yourself.
Unfortunately my local inspector confirmed that they don’t make exceptions, however, after you have the inspection done, he said it is out of his purview as to things people do after the fact. Like swap out the breaker 
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This is exactly what my electrician recommended.
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Kyle,
I installed a GFCI circuit breaker for my 240Volt spindle. The circuit breaker is installed inside the power panel. This circuit is only for my 240V spindle. And yes it passed inspection
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GFCI should have NO IMPACT to a CNC. Something is tripping a legit breaker. ARC Fault is another issue when LARGE motors are involved. Something is wrong and an override is not the solution.