GFCI Tripping on Inrush

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J

jtester

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Location
Las Cruces N.M.
I called for a 120 volt 20 amp receptacle in a commercial juice bar to be GFCI protected. The refrigerator in this location trips the breaker and the manufacturer says it is due to inrush. I thought this problem had been resolved with newer GFCI receptacles.

What experiences are others having recently?

Thanks

Jim T
 
jtester said:
The refrigerator in this location trips the breaker and the manufacturer says it is due to inrush.
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Thats bull, a GFCI operates by looking for a current imbalance on the circuit conductors, any inrush current will be equal on each of the circuit conductors.

If you have checked the circuit for all other problems tell them to come and pick up there machine and you will get one that is designed to work correctly.


Really.

GFCIs are being required in more and more places, the appliance manufacturers are going to have to adjust to this.
 
I-wire is right. I had a company claim that our GFI's were bad and the inrush on their microabrasion machine was tripping them. Went down there with a new GFI in a 4sq and a temp cord. Plugged two heat guns into it and showed the owner of the salon 25 amps on my probe. Those companies always claim that. It's like the Hot tubs companies always saying it's wired wrong when the board on the tub is bad. Give em hell :D :D
 
How old is the fridge?
Newer appliances now have a revised UL standard that requires them to have less "leakage" current. If the fridge is old, the existing wiring in the fridge itself could be causing the leakage current to trip open the GFCI device.
Otherwise it is most likely an issue with the fridge itself.
There are leakage current detectors available to test the appliance. Maybe you can borrow or rent one just to satisfy yourself and your customer.
 
Thanks for all the replies. The receptacle is gfci, not the breaker, and the fridge is new. This contractor is notorious for going to the local discount store and buying material. I'm going to check the brand of receptacle.

Thanks again

Jim T
 
i had a freezer and frig tripping two gfci outlets in a comm kitchen. so i changed them out with new ones and some thing happened they tripped.
so reading the spec on the appliances, the manufacture booklet said not to install gfci outlets do to nascence tripping. inspector said as long as its in writting its ok!!
 
The inspector is wrong. The directions on a piece of equipment do not give permission to violate the code. Since you knowingly violated the NEC you are liable if someone gets hurt, as is the inspector. If this equipment manufacturer does not allow their equipment to have GFCI protection, then it cannot be installed in a "non-dwelling kitchen" and connected via a cord and plug. There are NO EXCEPTIONS to the GFCI requirement for receptacles in commercial kitchens. We and the manufacturers will need to learn to live with it unless the NEC is changed.
 
haskindm said:
If this equipment manufacturer does not allow their equipment to have GFCI protection, then it cannot be installed in a "non-dwelling kitchen" and connected via a cord and plug.
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I agree 100%.
 
i agree, how ever in VA it passed my inspection-it wouldn't had it kept tripping. plus $1200 bucks in spoiled food. inspector said as long as its not accessible and had a single outlet he would let it fly.
 
greenjeans said:
i agree, how ever in VA it passed my inspection-it wouldn't had it kept tripping. plus $1200 bucks in spoiled food. inspector said as long as its not accessible and had a single outlet he would let it fly.
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Well that is a misinformed inspector and it will be on you if anyone gets hurt inspection or not.

It is interesting that the reason this requirement is in the NEC is because a kitchen worker was killed touching....you guessed it....a refrigerator with a ground fault.
 
Greenjeans, welcome to Va. (where?), and how's the Captain?

The inspector is wrong, and wrong to pass it. I've been having the same issue at a new (if I can say it?) Cracker Barrel that I didn't wire, but I've been asked to trouble-shoot in for the original EC.

There have been several appliances causing GFCI tripping, and I've repeatedly refused when asked about replacing the GFCI breakers with standard ones. They had to practically rebuilt one cooler.
 
haskindm said:
If this equipment manufacturer does not allow their equipment to have GFCI protection, then it cannot be installed in a "non-dwelling kitchen" and connected via a cord and plug. There are NO EXCEPTIONS to the GFCI requirement for receptacles in commercial kitchens. We and the manufacturers will need to learn to live with it unless the NEC is changed.
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I agree as well.

I don't understand how manufacturers are so behind on the NEC requirements.

I wasn't involved much with this job, but my company just finished a restaurant, and weren't required to put the appliances on GFCI if they were twistlock connected. :roll: I and the J-man doing this job (Usually a sharp guy) argued a bit over this, and I pointed out what Bob pointed out - this requirement was due to a person dying, but the "twistlock makes it OK" was too intrenched in his head. Evidently in the inspectors as well.

(As far as I know, the jurisdiction has no amendment altering 210.8(B)(2))
 
but the "twistlock makes it OK"
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Maybe that would be a reasonable exception. If the EGC is connected to the electrical system and to the frame of the equipment, there is much reduced need for GFCI protection. A properly installed and functioning EGC can prevent shocks, while all a GFCI can do is to limit the duration of the shock.
Don
 
Don, I agree that would be a reasonable exception and that proper grounding is much more effective than GFCI protection; but the fact is that there is no exception in the present code that allows such an installation. Until and unless the NEC is changed, any non-GFCI receptacle in a non-dwelling kitchen is a violation and the installer will be liable if someone is hurt. If the inspector is going to give "special permission" the electrician will need that permission in writing.
 
don_resqcapt19 said:
Maybe that would be a reasonable exception. If the EGC is connected to the electrical system and to the frame of the equipment, there is much reduced need for GFCI protection. A properly installed and functioning EGC can prevent shocks, while all a GFCI can do is to limit the duration of the shock.
Don
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I agree that there may be a reduced need for the GFCI protection, but it does not eliminate the need.

A low level ground fault within the appliance may not be picked up by a standard circuit breaker, but will be picked up by a GFCI protected circuit or receptacle.
It seems to me that with new appliances/revised standards that this should not be an issue.
If the appliance trips the GFCI protection (and not the standard breaker), would it not make sense that possibly there is some kind of ground fault within the appliance????
 
greenjeans said:
i had a freezer and frig tripping two gfci outlets in a comm kitchen. so i changed them out with new ones and some thing happened they tripped.
so reading the spec on the appliances, the manufacture booklet said not to install gfci outlets do to nascence tripping. inspector said as long as its in writting its ok!!
Click to expand...

There is no such thing as "nuisance tripping". Either the device is defective or there is a "reason" for the tripping. This applies to both GFCI receptacles or breakers, and standard circuit breakers.
 
If there's no such thing as "nuisance tripping" there sure is lots on the net covering the subject! Mostly refering to the cause being harmonics.
 
Pierre,
I agree that there may be a reduced need for the GFCI protection, but it does not eliminate the need. A low level ground fault within the appliance may not be picked up by a standard circuit breaker, but will be picked up by a GFCI protected circuit or receptacle.
Click to expand...
A "low level" ground fault with a functional EGC is not a shock hazard. The only voltage on the case of the equipment in that case would be the voltage drop on EGC from the "low level" fault current.
Don
 
I am puzzled as to how harmonics would create nuisance tripping. Just because a term is in frequent use, does not make it accurate. If a breaker is tripping because it is overloaded (even if the overload is due to harmonics) it has done its job. That is not a nuisance trip. Since triplen harmonics are additive on the neutral conductor, I can see how they may cause the neutral to become overloaded; but since we do not usually install overcurrent protection on most neutrals, how does this lead to nuisance tripping?
 
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