GFCI for commercial kitchen with equipment that is not compatible

[Bs1211]

Hello.
I have been scouring the internet high and low for information on this and cannot seem to find any. Thanks for having this forum site as it looks like I might get some help from a large community.

I need help with the NEC code that pertains to GFCI’s in commercial kitchens. This starts in 2017 with the NEC 210.8(b)(2) and is revised in more current years.

I had some issues with toasters with rope heaters where they absorbed moisture on the boat ride over from China. We were able to “burn off” the moisture and the manufacturer placed them in bags with desacant (those little silicone bags to absorb moisture) to prevent it.

Now, I’m dealing with a large ice cream machine. From what I’m being told, the machine uses an inverter which is not compatible with any type of GFCI. When I talk to the manufacturer, they share this feedback. It is UL, NSF and all kinds of other certified with stickers and logos up the wazoo.

So, any of you experts out there have any ideas? Throw away the machine? Hot wire the outlet or machine? Is there a way to get a variance on the NEC code based on machine comparability?

I understand from deep email conversations with the OEM, they indicate it is just not compatible with the current code. Does anything ever get grandfathered?

I ask since this isn’t a cheap piece of equipment to replace.

Thanks in advance for your help everyone!

 

[roger]

We will allow this since it is not a "how to" question.

In short if the manufacturer can not make a product that will work with proper (code mandated) wiring then it's junk and trash.

 

[augie47]

A variance would be a local AHJ call but it is doubtful one would be granted as GFCI is a safety issue and the problem is your equipment.
Hard wire could be a solution.

 

[kwired]

We will allow this since it is not a "how to" question.

In short if the manufacturer can not make a product that will work with proper (code mandated) wiring then it's junk and trash.

The other part of the problem is these machines did comply with leakage standards but then NEC suddenly threw in the GFCI requirement that now is not compatible with the leakage requirements. Newer products may eventually be designed to work with a GFCI (listing standard may take time to catch up) but at same time you have all this older equipment that technically has no defect but is still not compatible with current requirements.

Anything with an electronic motor speed drive has high probability of not being compatible with GFCI's.

 

[winnie]

The 'electrical code' is actually just a suggestion (not a law) until and unless it is adopted as law by a government as law.

So to get a variation on the code the first step is to figure out what the adopting authority is, and then find out from them what their policy is on variances.

The specific issue here is that VFDs use high frequency switching, and the high frequency causes current flow through insulation (really capacitive current flow, not leakage of electrons), which can trip GFCIs.

This is a multifaceted problem. A manufacturer could reduce this leakage, but that would cost money. I recall a claim that some GFCIs are excessively sensitive to high frequency leakage, but can't give specifics. Finally code may be overreacting in this case, because we'll defined leakage on the EGC is not in my opinion a safety issue.

I am a proponent of GFCIs which permit greater leakage if and only if the GFCI also verifies an intact EGC (ground wire).

In many instances, hard wiring an appliance removes a GFCI requirement, because it is assumed the EGC will be more reliable. Even if code doesn't give that out for a particular situation, the adopting authority might be more comfortable with that variance.

Jonathan

 

[roger]

The other part of the problem is these machines did comply with leakage standards but then NEC suddenly threw in the GFCI requirement that now is not compatible with the leakage requirements. Newer products may eventually be designed to work with a GFCI (listing standard may take time to catch up) but at same time you have all this older equipment that technically has no defect but is still not compatible with current requirements.

Anything with an electronic motor speed drive has high probability of not being compatible with GFCI's.

The OP did not say how old the machine is but the commercial kitchen GFCI requirement came into play in 2008 so manufacturers have had 16 years to come up with some type of solution. The GFCI requirements will continue to get more stringent.

I was involved with a commercial kitchen that had similar issues and the AHJ would not budge so the solution was to go with a different manufacturers equipment that worked a little (not flawlessly) better with GFCI's.

 

[kwired]

The OP did not say how old the machine is but the commercial kitchen GFCI requirement came into play in 2008 so manufacturers have had 16 years to come up with some type of solution. The GFCI requirements will continue to get more stringent.

I was involved with a commercial kitchen that had similar issues and the AHJ would not budge so the solution was to go with a different manufacturers equipment that worked a little (not flawlessly) better with GFCI's.

For some reason can't access the free online NEC versions to check this, but wasn't it initially just for 15 and 20 amp receptacles? Before then they still required within 6 feet of sinks I'm pretty sure.

I'm thinking it was later changed to include up to 50 amps @ 150 or less to ground for two pole circuits, and then later three phase was also introduced. So some equipment hasn't has as much time as other equipment has had. And other than dishwashers, pretty much anything in that kitchen can get around the GFCI requirement if it is not cord and plug connected.

 

[LarryFine]

In many instances, hard wiring an appliance removes a GFCI requirement, because it is assumed the EGC will be more reliable.

It's generally because a receptacle is installed that GFCI protection is required for kitchen personnel plugging and unplugging appliances.

 

[don_resqcapt19]

We will allow this since it is not a "how to" question.

In short if the manufacturer can not make a product that will work with proper (code mandated) wiring then it's junk and trash.

That is a bit unfair since the product listing standards have not caught up with the huge expansion of GFCI requirements in the NEC.
In addition, there are tripping issues with some GFCI as a result of high frequency leakage current that does not exceed 5 mA. The UL 943 committee is working on modifying the product standard to address this high frequency leakage current, but that is a process that takes at least as long as a code change cycle. There will continue to be GFCI issues until the product standards catch up to the code and until the new GFCI requirements in UL 943 are completed and compliant devices hit the market.

 

[roger]

You are right Don, calling them junk and trash was little harsh, and I am thinking cord and receptacle commercial counter type appliances. I don't really know what the equipment is.