I have a personal bowling ball cleaning machine that states "plug to a non-GFCI outlet" which means it has built-in GFCI however, in the area I am living, all receptacles must be GFCI protected and this comes from the main breaker board to every receptacle in the facility. So whenever the machine is plugged in, the breaker goes off.

Firstly, are GFCI equipped machines supposed to work when plugged into GFCI protected circuit? If not, is there a way to connect GFCI equipment to GFCI receptacle by by-passing through, say a transformer, between the cleaning machine and the receptacle? I want to stay away from doing tricks at the receptacle level as I would think the circuit itself will detect and will not work.

I really need help here, thank you so much for any help you can give me in advance!

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    A GFCI protected machine should work with any GFCI outlet, are you sure the machine is GFCI protected, Some types of systems have large leakage currents and they will trip a GFCI every time the motor cycles up and down due to the harmonics generated (leakage). that may be the reason the machine trips GFCI circuits, A true Isolation transformer would eliminate the GFCI from tripping but then the frame of your machine would possibly have a voltage while running (not safe). – Ed Beal Dec 14 '15 at 18:00
  • Thank you Ed! Checked with manufacturer and they say the machine has on-board GFCI. Their explanation was that on-board GFCI don't work on GFCI circuits. I am living in Asia, and all of those who purchased the machine in this region are having exactly the same problem. The machine has a water tank which heat ups to 50degrees (C) on start-up so the leakage you mentioned is a high possibility - also, tolerance of the on-board GFCI is much higher than the receptacle/circuit? I am not an expert in electronic, can you shed some light as to what an isolation transformer does? – Hammersmyth Odeon Dec 14 '15 at 20:26
  • An 1:1 Isolation transformer is a transformer that takes the line voltage and transforms an isolated voltage of the same value. Hospitals use them in the U.S. to make sure the power they are using has no neutral voltage. The neutral to ground is monitored (I don’t remember the alarm threshold). Isolation would be 1 way to stop your home GFCI from tripping but I would caution that the system has the possibility to have a voltage on the frame this is why isolated systems are monitored. the transformer would need to be as large in watts as the machine, I usually over size transformers. – Ed Beal Dec 14 '15 at 21:52

There is no reason one GFCI should cancel out another GFCI. Don't trust that the device is GFCI-protected unless it specifically states so. As Ed Beal mentioned in his comment, it seems likely that the device is actually leaking current, and thus causing a (not unreasonable) trip in your GFCI-breaker.

My advice would be to call the maker of the device to ask specifically why it states not to plug into a GFCI outlet. They should also be able to tell you what they recommend you use, since you don't have a non-GFCI outlet.

If, as you mention, the GFCI protection is in your breaker, you are correct that there aren't any outlet tricks you could perform to create a non-GFCI outlet, and in most cases you should avoid removing this protection anyways.

UPDATE: I'm updating my answer in response to more information from the OP in comments.

Since you have confirmed the device has it's own GFCI, I would recommend calling your local planning/permitting authority, or a licensed electrician, and asking them what your options are. It may be possible to install a dedicated outlet, or perhaps hard-wire this device, within code. Without knowing exactly what your local code is, I can't recommend any other action.

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  • Hi Ench, thanks for your input. Their manual specifically says plug into non-GFCI outlet and I was told by their technician that it has an on-board GFCI. Given that the machine uses water pump/heater, if the machine has no on-board GFCI and to be plugged in to non-GFCI outlet, in reverse, wouldn't that be very dangerous? – Hammersmyth Odeon Dec 14 '15 at 20:37
  • I'm not sure I'd use the phrase "very dangerous" but yes, if it lacked a GFCI, and told you to avoid a real GFCI, I would be very leary of plugging this thing into my home. I'm still a little concerned about what they are saying. If they have a GFCI in their machine, but it's tuned/set not to trip for certain amounts of leakage, the question comes down to how much you trust the company. A household GFCI is a safety feature, and one that can be very important in certain circumstances. – ench Dec 14 '15 at 20:47

There's no problem have GFCI devices protected by other GFCI devices.

The problem is that the machine; for wherever reason, is designed in a way that causes it to trip GFCI devices during normal operation. The manufacturer states not to use the equipment on a GFCI protected circuit, not because it contains a GFCI device, but because it doesn't play nice with GFCI devices.

You'll either have to plug the machine into a non-GFCI protected circuit, or contact the manufacturer to figure out if there's a way to make it work.

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I agree with ench: "There is no reason one GFCI should cancel out another GFCI."

If the machine really has an in-built GFCI, then wouldn't it have user accessible TEST and RESET buttons? Hammersmyth Odeon did not mention a RESET button.

A circuit interrupt without a reset capability is called a FUSE.

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