GFCI outlet for pool lights keeps tripping

[pcm2a]

As soon as the pool/spa lights are turned on the GFCI breaker trips. I think I have checked everything possible and am now stumped.

The hot wire reads 120v with a multimeter.

Test #1:
1. Unhook the two wires from the output of the relay. These two wires go to the spa and pool lights.
2. Turn on the lights, the gfci is not tripped.
3. Plug up just one of the wires (either pool or spa lights)
4. Turn on the lights, gcfi is tripped
5. Swap for the other wire (either pool or spa lights)
6. Turn on the lights, gcfi is tripped

This was suspicious because it is unlikely that both the light in the spa and one of the lights in the pool leaked at the same time.

Test #2:
1. Replace the output wires from the relay (pool and spa lights) with the output wire for the blower
2. Turn on the lights, which should activate the blower
3. GCFI is tripped

This is also suspicious since the blower is working fine. At this point I think it must be the GFCI outlet.

Test #3:
1. Replace the GFCI output
2. Repeat Test #1
3. GFCI still trips

I think we now have eliminated the problem being the GFCI outlet?

Test #4:
1. Take out the relay for the lights and replace it with the relay for the blower (we know that the blower works fine)
2. Repeat Test #1
3. GFCI still trips

#Test #5:
1. Use the wire coming out of the circuit breaker for the blower, into the GFCI
2. Repeat Test #1
3. GFCI still trips

Now I've tried a different GFCI outlet, different relay, different breaker. The only thing I haven't been able to try is a different white neutral wire. They all come from the same block.

If anyone has any other ideas to try I would love to hear it.

 

[Jimrahbe]

pcm,

Did the lights originally work, or is this a new set up???

If new, I would assume you have the GCFI wired wrong.

Show us a drawing of how your GFCI is wired. Keep in mind there are input and output wires on a GFCI outlet.

Thanks,

Jim R.

 

[zea3]

Have you added or changed any equipment lately? Do you have a GFCI outlet wired to a GFCI breaker?

 

[pcm2a]

15 year old pool, not new. Issue noticed on Friday night. Will make a diagram of how it is wired, but I'm not sure how you could do it wrong. The new one has a light that comes on to tell you if it's ready to go or wired incorrectly.

 

[pcm2a]

Have you added or changed any equipment lately? Do you have a GFCI outlet wired to a GFCI breaker?

Nothing has changed in years. All of the breakers look the same, and it's wired to one of them. I'll double check them to see if anything is different about that one vs the others.

 

[ajw22]

Are you sure the lights are wired directly into your panel and not through a pool light junction box near the pool?

Please show us actual pictures of your wiring. People often describe or draw what they think they have which differs from what they actually have.

 

[Dirk]

I had to abandon the switch for my pool light. The wire that ran in conduit to the pool light was fine, still is. But when the wiring in a separate run of conduit that ran to the pool light switch was involved, the GFCI would trip. My troubleshooting pointed to the wire itself. My guess is that the conduit filled with water at some point and somewhere along its run there is a current leak, enough to trip the GFCI. Perhaps a nick in the insulation, or maybe the wrong type of wire was used, one that is not rated for wet locations? Not sure.

When you eliminate everything else, you can troubleshoot the underground wiring by bypassing it temporarily with a run of Romex above ground. If that solves the problem, then you'll know there's some current leaking underground somewhere in the buried wire.

I didn't bother to fix mine, so I'm not sure what to recommend for that. You could try pulling new wiring through the underground conduit, after somehow trying to blowout water that might be inside the conduit, but that may or may not solve the problem permanently.

Edit: Just read Allen's post. I was assuming you have such a junction box. If the wires coming off your light fixtures run directly to the pad, then of course you wouldn't be able to use a temporary bypass as I suggested.

 

[ajw22]

Show me pics of where the neutral on the LOAD side of the GFCI outlet connect to.

 

[ajw22]

#Test #5:
1. Use the wire coming out of the circuit breaker for the blower, into the GFCI
2. Repeat Test #1
3. GFCI still trips

Unless you also moved the neutral for the blower to the GFCI LOAD connection this test was invalid.

Both the hot line AND the neutral for a 120V load must be connected to the GFCI for it to work. If the neutral is misconnected then it will always trip.

 

[pcm2a]

Unless you also moved the neutral for the blower to the GFCI LOAD connection this test was invalid.

Both the hot line AND the neutral for a 120V load must be connected to the GFCI for it to work. If the neutral is misconnected then it will always trip.

This may be the issue. Let me do some testing and report back.

I've decided that I want to take all of the pool controls out of the testing. What I've done is wired up an extension cord into a gfci outlet. I can plug things in and know that it's on and working. Now it sounds like I need to plug in the hot and neutral wires to <anything> to have it turn on for a test.

 

[pcm2a]

Show me pics of where the neutral on the LOAD side of the GFCI outlet connect to.

I will try to see where that wire runs. If there is a junction box for the pool lights then I have no idea where it is. I'll look around for it.

 

[pcm2a]

Thanks a ton for the help so far. I now know that there is nothing wrong with the GFCI outlet. I tried chaining it to another one and the outlet is working fine. All of my tests were probably a waste of time.

There is one junction box in between the equipment and the pool. Attached is a photo of inside it. There is even some pool and spa text written on it. I tested continuity between the LOAD neutral wire for the lights and the bundle of white wires in the photo. There was continuity between them.

Are some of those neutral wires to the pool and spa lights? There is one spa light and two pool lights. I assume if they are, I could test each one and figure out which one is causing the problem?

I can heat up the spa and pull the light out and inspect it. It's too cold still to get to the pool lights.

 

[ajw22]

You need to identify which wires are the hot and neutral from your panel.

And identify the hot and neutral wire from each of your three lights.

Label all the wires as you go along.

Then wire nut together the panel hot and neutral to one light and turn it on and see if the GFCI trip.

Do that for each light and report back the results.

 

[pcm2a]

Should I do that with trial and error to find the hot/neutral for each light?

One thing that is puzzling is there is 5 wires bundled but there are only three light fixtures. That leaves one additional set of wires that I' not sure what it could go to.

 

[ajw22]

Should I do that with trial and error to find the hot/neutral for each light?

Each light wire should be coming up into the junction box in its own conduit. I was hoping the writing in the box would identify which light each conduit runs to.

Using your ohmmeter you may be able to see which hot wire and neutral gets a reading saying they are connected.

One thing that is puzzling is there is 5 wires bundled but there are only three light fixtures. That leaves one additional set of wires that I' not sure what it could go to.

The puzzles of inheriting construction.

 

[pcm2a]

Once I started investigating the junction box everything was very clear. There are three conduits for the three lights, they are labeled. There is a 4th that goes to a landscape lighting power box, but currently there are no lights hooked up to it.

Test #1:
1. Hook each light up individually.
2. Leave on for a few minutes.
3. All three lights work individually!!!

Test #2:
1. Hook pool light #1 up to pool light #2
2. Leave on for a few minutes.
3. Both lights working.

Test #3:
1. Hook pool light #1 up to spa light
2. Leave on for a few minutes
3. Both lights working
4. Repeat for pool light #2 and spa light

Test #4:
1. Hook all three lights up together
2. GCFI tripped

Any ideas why individually or two are working, but not all three together? My two pool lights are china led bulbs from amazon that you screw into the housing and can change the color with a remote. They have been in there for around 4 years. Maybe one of them is pulling two much? The spa light also can change colors but it's a $5 bulb.

 

[Dirk]

Possible: a GFCI will trip when a certain threshold of current leakage is exceeded. Perhaps more than one (or all three) of your lights (or their cables) are leaking current to ground. Individually the leak is not enough to trip the GFCI, but when combined it is.

 

[ajw22]

Dirk pretty much explains it.

A Class A GFCI trips when the current to ground has a value in the range of 4mA to 6 mA (reference UL 943).

The problem with multiple lights on one circuit is that each light can leak 2 mA without tripping the GFCI. But when all 3 lights are connected it exceeds the threshold for a GFCI trip.

How old are the lights? Over time insulation breaks down and leaks some current and moisture gets into the light housing.

Replacing the lights will probably fix it. You can replace them one at a time and see if replacing one or two stops the trip.

Or you can disconnect one pool light and run it with one pool light and one spa light.

 

[pcm2a]

Is there any good way to test/troubleshoot which set of wires, light fixture, or bulb could be the issue without having the light fixtures out of the pool? For now I've left the two pool lights hooked up and turned on to see what happens.

Once it's warm enough to get the fixtures out I could try different bulbs and see what happens with trial and error.

 

[pcm2a]

How old are the lights? Over time insulation breaks down and leaks some current and moisture gets into the light housing.

Replacing the lights will probably fix it. You can replace them one at a time and see if replacing one or two stops the trip.

I put the bulbs in about 4 years ago, along with new seals at the same time. Maybe enough moisture has gotten into one of them to cause this problem but not enough to break the bulb?

The spa light gets used regularly and I'm sure that light takes a lot of kicks from little kids feet. What I'll try next is pulling that light out and inspecting it. I have one extra seal so I could go ahead and replace that one. The other bulbs cost $70-80 each but can troubleshoot them once it's warm enough to get in the pool.