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My lights, when turned on, are tripping the GFCI after they have been on for about 5 minutes. I have Jandy dimmer relays installed between the GFCI and the light circuit. Has anyone else had this problem? I changed the GFCI and it still does it. It seems odd to me that there would be a delay, because if there were a ground fault, it would be instant. Anybody got any ideas?
You are thinking like I would. Changing the GFCI would have been my first and second guess. The delay seems really odd. Once it trips, what happens when you reset it? Another 5 minute delay? Sure doesn't sound like a ground fault if so.Quote:
Originally Posted by craiga
Is it an outlet or a breaker type GFCI?
Anything else on the line that could be causing an unusual load?
I think you are looking in the wrong place. GFCI doesn't pop under load--that's the breaker's job. GFCI detects an imbalance between the poles and shuts down. I think the GFCI is doing EXACTLY the job it's supposed to do--shut down when there's a ground fault.
It sounds like you have a short somewhere in either the lights or the Jandy dimmers. I would start testing there. It also sounds like it's an intermittent short, too. I would STRONGLY recommend you not use the pool until the problem is solved or the lights are completely disconnected from all electricity, either by unplugging or if hardwired, removing the wiring.
Why do people always assume that when a breaker or GFCI keeps popping its a bad breaker or GFCI, not that they are doing their job of protecting you?
John, it is an outlet type GFCI, and after reset another 5 minute delay occurs. Nothing else on the line except the lights. I did find out however that there was thunderstorm/lightning occuring just prior the this problem surfacing (I was out of town). Maybe these dimmers are fried, but still the delay sounds like something is heating up and then causing the problem. Carl, I know i have a problem and don't doubt that the GFCI is doing its job. I changed it because i wanted to eliminate the possibility of it being bad. I have had a couple of them go bad before, so i know it is possible. It is quick, easy and cheap to replace one, and if that is not the problem and you find yourself with a spare, no big deal.
Thank you both for your replies.
A short won't trip a GFCI breaker unless it is a hot to ground short (also known as a ground fault). A "normal" hot-neutral short will trip the circuit breaker. GFCI's trip when the current in the neutral is different from the current in the hot line. That's something that usually doesn't change during operation unless there is movement that causes a ground fault. 99 times out of a hundred a situation like this is a bad GFCI.Quote:
Originally Posted by CarlD
A possibility is a damaged neutral wire or loose connection that is heating up and conducting poorly. Worth a look.
i did a little more testing and found that the problem only occurs in the pool light circuit and not in the spa light curcuit (there are seperate relays for each). Also, the pool light curcuit only trips the GFCI when the lights are on at 100%. Anything dimmer (75% and lower) does not trip. Any thoughts?
Are the relays the same so you could try swapping them? I'd guess you're on the right track, but swapping them could prove it.
John:
Yes they are the same. Good idea; I'll swap them and see what happens. Thanks for your reply.
Swapped them and no change. I guess that rules out the dimmer relay. Shouldn't there be a junction box somewhere between the light and the panel? I have never seen/noticed one.
There's often a box behind the light above the ground about 12". Interesting (and I'm sure aggravating) problem. Does anything else share this circuit, particularly after the GFCI?Quote:
Originally Posted by craiga
John; i couldn't find a junction box and finally called the builder and was told there is not one. Nothing else on that circuit except the pool lights, which are two (500 watt) lights. I threw in the towel and placed a service call to the builder's electrician to come look at it. i'll let you know the results.
Well, pool repair guy came out and said there is a small amount of water inside the light assembly. Dosen't know if the gasket is leaking or the assembly is cracked. Reccomends replacing entire assemly instead of just the bulb (which would come with a new gasket). Said the reason it only tripped on 100% was because any other setting did not draw enough amps to trip the gfci. Just thought this info might be helpful to someone else with a similar problem.
That scares me a little, because the GFCI trips at just a few milliamps, and does so almost instantaneously. I can't come up with an explanation for the time delay, particularly the fact that it took the same time to trip when the breaker was reset. The water is there, the bulb is hot and the dimmer is at whatever temperature it is going to stabilize at. I could see it tripping after 5 minutes the first time, and then much more quickly upon resetting.:confused:Quote:
Originally Posted by craiga
Glad it's fixed, but still a puzzler. I would have assumed (incorrectly apparently) that water would have given an instant trip.
Well, I'm with you. Kind of blows the way i thought a gfci would work. I would have thought that once water penetrated the assembly, it would trip the gfci instantly upon any current being transmitted. Its not like the water ever drains out and the thing dries out before the next test. Its not fixed yet though, repair guy has yet to replace the light assembly and test his diagnosis.
Have you replaced the GFCI, to ensure it's not failing?
The only other thing I can think of is there aren't enought minerals in the water to allow it to pass much of a current, so there isn't enough to trip the GFCI until the level is 100%. Or you are getting a capacitor action that discharges and trips it.
But a GFCI should trip at the slightest imbalance in the poles...but it's 12v right?.......
Carl,
Sorry for the delay in this reply, i've been unable lately to check the forum. Yes, i replaced the GFCI and eliminated it as the problem. Pool Guy also did the same thing and found no problem with it. The system is 120v. Its still not fixed yet, but the pool guy is going to replace the light assembly and bulb.