# GFCI Tripping



## Dennis Alwon (May 9, 2009)

Try a different brand gfci but my bet is that one of those pieces of equipment has an issue


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## ELECTRICK2 (Feb 21, 2015)

6506gary said:


> We have a project that has a GFCI feeding a small computer UPS that has a desk top computer and a laboratory machine with a 1/2 HP motor for mixing a water solution plugged into the UPS that trips when everything is running. I initially thought it was the UPS, so I took it out of the circuit leaving the computer and the laboratory machine and it still trips. If it is the computer or the lab machine, they will not be able to use the GFCI because the computer runs the lab machine. I might add that the circuit worked fine before adding the GFCI and after adding the GFCI with no load on it. Any ideas?


I'm assuming it's 1 recept both units are plugged into.
Plug one unit into a different recept on a different circuit with an extension cord. If GFI still trips, swap them. If it still trips could be a bad GFI.


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## Sparkchaser1 (May 17, 2015)

Will your AHJ allow you to install a single recep for the UPS instead of the GFCI?


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## macmikeman (Jan 23, 2007)

Can I ask why is a gfi considered for this machine in the first place? 

(actually not a bad idea, since it sounds like either your ups, or your mixer, or a cumulating of both, is leaking current)

Is the machine located outdoors? In a garage? In a dwelling bathroom? Is it part of a vending machine or perhaps a drinking fountain? Indoor wet location? Where does the gfi come into play in this? Manufacture instructions perhaps?


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## oliquir (Jan 13, 2011)

it has no sense since even if the gfi trips the ups will continue supplying electricity. If a gfi is needed for the machine security it must be after the ups


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## 6506gary (Sep 20, 2010)

The reason for the GFCI is the insurance company and because of the presence of water, they want to protect all devices at this lab station.. This is an indoor laboratory application.


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## emtnut (Mar 1, 2015)

6506gary said:


> The reason for the GFCI is the insurance company and because of the presence of water, they want to protect all devices at this lab station.. This is an indoor laboratory application.


Did you try what electrick2 suggested ? What were the results ?

It may be the UPS or PC ... read this:
http://www.schneider-electric.us/si...ang=en&id=FA158850&locale=en_US&redirect=true


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## pete87 (Oct 22, 2012)

6506gary said:


> The reason for the GFCI is the insurance company and because of the presence of water, they want to protect all devices at this lab station.. This is an indoor laboratory application.




Insurance Company ... They are not the NEC ... or AHJ .

( check for N hit G in Plug Strip ) if equipped .


unrelated story ... Way back in the 90,s ... i wired a Restaurant ... floor in kitchen was remodel with Epoxy Surface up the side walls also , like in a Hospital with Cove Joints.

A year later ... I was checking out the waitress butts and eating free meatballs 
when they were doing the Mats ... in the kitchen ...

I Blew a Gasket ... The workers were Standing in , 8 - 10 inches of Water , cleaning the mats ... A POOL !!!



Turns Out that the , " Town Agency " thought that washing the Mats Out Back was , " Unsightly to the Parking Lot "




Pete


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## splatz (May 23, 2015)

Do you know whether it's a line interactive UPS or an online / double conversion? 

I am betting on the half hp motor as the culprit.


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## emtnut (Mar 1, 2015)

pete87 said:


> A year later ... I was checking out the waitress butts and eating free meatballs
> when they were doing the Mats ... in the kitchen ...
> 
> I Blew a Gasket ... The workers were Standing in , 8 - 10 inches of Water , cleaning the mats ... A POOL !!!
> ...


I wouldn't have noticed the water in that situation :laughing:


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## kbatku (Oct 18, 2011)

Unrelated, but I've had electronic ballasts trip GFI's.


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## ELECTRICK2 (Feb 21, 2015)

6506gary said:


> We have a project that has a GFCI feeding a small computer UPS that has a desk top computer and a laboratory machine with a 1/2 HP motor for mixing a water solution plugged into the UPS that trips when everything is running. I initially thought it was the UPS, so I took it out of the circuit leaving the computer and the laboratory machine and it still trips. If it is the computer or the lab machine, they will not be able to use the GFCI because the computer runs the lab machine. I might add that the circuit worked fine before adding the GFCI and after adding the GFCI with no load on it. Any ideas?


Any updates as to the outcome?


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## joebanana (Dec 21, 2010)

Is the "lab machine" a refrigerating unit? Some motors are notorious for tripping GFI's when they turn off (back emf). If it's a brushed motor, arcing could be the problem. Try plugging the motor into a different circuit.


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## pete87 (Oct 22, 2012)

joebanana said:


> Is the "lab machine" a refrigerating unit? Some motors are notorious for tripping GFI's when they turn off (back emf). If it's a brushed motor, arcing could be the problem. Try plugging the motor into a different circuit.




I think he is there with a old motor or he should follow the cords into machines for a N to G fault ... usually right there .

or

The UPS thing 



Pete


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## Sparkchaser1 (May 17, 2015)

pete87 said:


> Insurance Company ... They are not the NEC ... or AHJ .


They sure aren't, but they don't care, they want what they want, whether or not it makes sense. Homeowners with fusible services that change insurance companies are often required to switch to breaker panels, even though a fusible panel in good shape and fused properly is just as safe or safer that a breaker panel.


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## chknkatsu (Aug 3, 2008)

pete87 said:


> Insurance Company ... They are not the NEC ... or AHJ .
> 
> ( check for N hit G in Plug Strip ) if equipped .
> 
> ...


this reminds me of a video Mike Rowe made called "safety 3rd". I suggest everyone here check it out.


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## nrp3 (Jan 24, 2009)

I've seen the ballast thing in apts that were old enough to have the oversink light, a strip fluorescent, trip the GFCI receptacle when it was turned off. Didn't happen often. A switch from Leviton to P&S solved the problem. Might here depending on brand of GFCI. GFCI breaker. Though I'm not found of using those when there is a long home run.


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## pete87 (Oct 22, 2012)

chknkatsu said:


> this reminds me of a video Mike Rowe made called "safety 3rd". I suggest everyone here check it out.



Safety 3rd ... Excellent ...


You know i will check out the waitresses ... He only hired 10's and 9's with an 

8 ... Real Fine Gals ...

I got called to service a recpt. in that kitchen , all EMT job ...I wired the Job .

It was blown to hell in the wiring ... Like a router cut the wires like some sheet rockers do ... then turned on several times !

I knew something was up ... but not what ... so I Went back to see what was happening there ... I never have problems with my jobs ... The Kitchen Help will say nothing ... 


A POOL !!!!!

Lucky No One Died .



Pete


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