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TexasTurfgrass
12-27-2010, 09:07 PM
I installed a CAST transformer (1200 W) for a recent project and the GFI that the transformer is on continues to flip. The person who I installed it for also has a lot of Christmas lights in the front and the back that are on the same circuit. I have tested the amps on the transformer and it is not close to capacity. I am hoping that the circuit has been overloaded with the Christmas lights, but it is hard to tell since they were tuned on at about the same time.

Just trying to rule out a few things so my question is if for some reason there is a short in the wiring, water is getting on a splice, or the well lights are getting water on them the transformer will flip before the GFI flips, correct? I feel dumb about having to ask this question because I know the answer but I have thought about this problem until I may have convinced myself otherwise.

Thanks,
Mark

ccfree
12-27-2010, 10:02 PM
I installed a CAST transformer (1200 W) for a recent project and the GFI that the transformer is on continues to flip. The person who I installed it for also has a lot of Christmas lights in the front and the back that are on the same circuit. I have tested the amps on the transformer and it is not close to capacity. I am hoping that the circuit has been overloaded with the Christmas lights, but it is hard to tell since they were tuned on at about the same time.

Just trying to rule out a few things so my question is if for some reason there is a short in the wiring, water is getting on a splice, or the well lights are getting water on them the transformer will flip before the GFI flips, correct? I feel dumb about having to ask this question because I know the answer but I have thought about this problem until I may have convinced myself otherwise.

Thanks,
Mark
Mark,

If the GFI is tripping, it could be caused by moisture on the plug or just a bad GFI. The secondary breaker on the transformer will trip if you have a short or an overload. The breaker in the electrical panel will trip if the added Christmas lights exceeds the amp capacity of the breaker.

I am in the Dallas Ft Worth area and can help you if you are local or I can troubleshoot it with you over the phone.

steveparrott
12-28-2010, 10:02 AM
I agree, overload is not the problem here since GFI's should only trip due to a ground fault - the most likely cause is the christmas lights, possibly a wet socket or exposed wire making contact to ground.

TPnTX
12-28-2010, 10:09 AM
To answer your question Yes you are correct. A line from your transformer going to ground should not trip the GFI the trans is plugged into.

Is is random? only on startup? what are the details?

TexasTurfgrass
12-28-2010, 06:47 PM
Thanks for the replies everyone.

I went back today and ran a few tests. I will able to reproduce the issue by running the irrigation system and it turns out it was in fact the Christmas lights. The person who installed them didn't tape the female ends and when they got wet it caused the GFI to trip.

Typing this just made me realize how dry it has been here this winter.

Thanks again.

Mark