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salvador
GFIC outlet in work shed

Greetings all, I've recently installed a breaker box in my shed and GFCI outlets however, every time I turn on my air compressor it trips the breaker. I have a 20amp breaker feeding the GFIC line side and an additional regular outlet being fed from the GFIC load side (which is where I have the air compressor plugged in. Recently I changed the circuit breaker from a 10 amp to a 20amp hoping this would help...it did not. The only other thing I can think of is that I don't have an actual grounding wire in the ground to provide a true ground, can this be my problem?? Your advice or suggestions would be greatly appreciated.

JLMCDANIEL
Re: GFIC outlet in work shed

The ground wire is not the problem, in fact a GFCI does not require a ground to work. The problem is that you have the outlet wired to the load side of the GFCI. You compressor is most likely a capacitive start motor. The capacitor causes a delay in the current flow between the hot and common so the GFCI trips. Wire you 2nd outlet to the power side of the GFCI (that's direct to the power and not through the GFCI)) and the GFCI won't trip. That's a common problem with GFCI's.
Jack

Ernie_Fergler
Re: GFIC outlet in work shed

And change the breaker back to the original one.
A ten amp breaker. Can you give more info on that one?:)

chromarado
Re: GFIC outlet in work shed

Salvador , Sounds like you had your receptacles wired correctly. The standard duplex receptacle should be wired off the load side of the ground fault type receptacle when it is in a shed. You changed your circuit breaker size to 20 amp. First make sure your wire size is 12 gauge(it will be stamped along the lenght of the wire) If it is indeed 12 than make sure you have installed a 20 amp ground fault type receptacle . If the neutral slot (white wire) is straight it is 15 amp and will act as a 15 amp breaker , so swap out with a 20 amp gfi . This will have a sideways " T " slot for the neutral.

JLMCDANIEL
Re: GFIC outlet in work shed

Perhaps I misunderstood. Is it the circuit breaker that trips or the GFCI that trips? How big is the compressor motor? What size wiring are you using?
Jack

Blue RidgeParkway
Re: GFIC outlet in work shed

when we electrified our shed we had to dig for a feeder thats why we needed a box. the garage didn't need a feeder because it was one circuit and we attached it with an addition from the back door to make a mud room.

anyways I wouldn't be using the compresser like a circuit tester heck i'd be suspecting the thing itself you shure its not shorting out or locked up:confused:

i'd guess the compressor is sucking more amsp then yr breaker when it starts maybe not enough juice gettin to the shed. i remember we had to use thicker because the distance from the main box.

Ernie_Fergler
Re: GFIC outlet in work shed
Blue RidgeParkway wrote:

when we electrified our shed we had to dig for a feeder thats why we needed a box. the garage didn't need a feeder because it was one circuit and we attached it with an addition from the back door to make a mud room.

anyways I wouldn't be using the compresser like a circuit tester heck i'd be suspecting the thing itself you shure its not shorting out or locked up:confused:

i'd guess the compressor is sucking more amsp then yr breaker when it starts maybe not enough juice gettin to the shed. i remember we had to use thicker because the distance from the main box.

Please run all this buy me again.:confused:

djohns
Re: GFIC outlet in work shed

Is the air compressor the only thing that will trip the breaker ? Have you tried the compressor at a different location to rule it out as the problem ?

Re: GFIC outlet in work shed

I hate to say this everyone has missed the main safty there is no ground. I would suggest a ground be installed it is a huge safty issue.

The what size service is in the shed? How far does the service run from the house? what size wire?
There could be a issue of voltage drop. As the voltage drops the current increases causing the breaker to trip. Motors on start up can draw up to 300% of its load till up to speed. Sounds like to me there is a huge drop in voltage due to the distance the wire was run from the house.

salvador
Re: GFIC outlet in work shed

Thanks for the tip Jack, I've wired the compressor directly to a power source and have eliminated all problems.

chromarado
Re: GFIC outlet in work shed

You have created an Shock Hazard by eliminating the GFI in shed .You have created a dangerous situation by wiring the compressor on the line side of the GFI. Yes of course this works now because you eliminated the 15 amp rated GFI inbetween , Please rewire GFI to a 20amp one and wire your standard duplex off the "load" terminals.

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