Outdoor GFI tripping under load

Old 07-03-15, 10:59 PM
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Outdoor GFI tripping under load

OK everyone I am stumped with my GFI curcut and need some help which is greatly appreciated.

Background into the circuit

I installed a dedicated outdoor curcut for my outdoor needs. It is 15 amp originally with the first outlet being a GFI outlet and the remaining outlets in my front yard being lights and a sprinker timer. The lines are outdoor wire that can be put underground. Over the years I have had to replace the GFI outlet I would say every three years as it started to trip more often.

So last month I wanted to fix the problem for ever so I installed a GFI breaker in the curcut box for this outdoor circuit removing the GFI outlet in the first box.

This is when my current problem started. The GFI breaker when in fine and tests OK when I manually trip it at the panel or out an outdoor plug. I can place a small load ( my cordless charger wihich only has a single light to it getting power) but under any kind of load the GFI breaker in the box trips. I have tried various loads with the same result and nothing else in plugged into the curcuit. Any ideas?

Thanks in advance for the help.
Old 07-04-15, 04:27 AM
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Gfi's do not trip from overloads. They trip because there is an imbalance between the outgoing and return current. It sounds like it is leaking somewhere . What materials did you use and how deep was it buried ?
Old 07-04-15, 05:58 AM
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Does it trip when you plug something into one of the other outlets or when the timer only comes on?
Old 07-04-15, 08:03 AM
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Moving the GFI from the receptacle to the panel didn't address your original problem which is like PC said.... a leak to ground.... and most likely underground.

If I was troubleshooting the circuit I would disconnect the white and black wires at the panel.
I would take an ohmmeter set to a high scale and check from white to ground and black to ground. There should be no indication of continuity. Any leakage to ground from either wire will cause the GFI to trip prematurely.
Old 07-04-15, 08:39 AM
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Gfi's do not trip from overloads.
In this case it could because the GFCI receptacle was removed and replaced with a GFCI circuit breaker. But, I think you are right, the OP is getting leakage in the circuit causing a ground fault.
Old 07-06-15, 10:12 PM
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Thank you everyone for your responses. Sorry for my slow response as I don't normally post a question then not respond although on the 4th of July my next door neighbor have an accident and was killed. Not fireworks but tree related and breaks our hearts as he had young family.

PJ I will try your idea and report back. Many thanks but if it is leaking it going to be a nightmare

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