GFCI randomly tripping

[nickmealey]

I've been working through setting up a RS650 (see build thread) but I've been having issues with my GFCI outlet randomly tripping that has been pretty frustrating. The strange thing I can't seem to figure out is that it's not consistent. I've spent a fair amount of time searching through articles and forum posts and the suggestions are pretty much all the same: start plugging each piece of equipment one by one and see what trips it. The trouble for me is that the tank will go weeks at a time without issue and then suddenly trip in the middle of the night, so I'm not sure the best way to eliminate the source of the issue one by one. Not surprisingly it seems most likely to trip after an evening that I've tinkered with something.

At first it tripped probably 3 times over the course of about a week and a half, all at night and several days apart. The outlet was a GFCI/AFCI and so I swapped it out for a standard GFCI thinking that the the arc fault was tripping it. I thought it was solved because it went a full two weeks before tripping again a few nights ago. It doesn't appear to be timer (but possible) related but always at night so far.

Last night I removed the "daisy chain" on the outlet so that it only trips for stuff on the tank directly, and a separate outlet for the fish room. I tested with a multimeter for any stray current by placing the common probe into ground and the red probe in the water, no current down to the most sensitive setting on the meter. I also attempted to create a temporary grounding probe (hooking up ground into the water) hoping the outlet more likely to trip consistently, but it didn't. I'll probably end up installing a third GCFI, but I need to get an Apex Energy bar before I do because the power is being fed through a single Apex EB. This would at least mean I could keep my MP40s and pumps on a separate outlet.

I've read that running too many appliances off a single outlet can be problematic, but I can say that I've run tanks with at least as much equipment off a single outlet without troubles. It's currently pulling less than 2amps, which is well under the 15amp outlet. Here's a list of equipment I have running:

Tank:
- Two MP40s (used)
- Two Gyres (used)
- Two return pumps (Reef Octopus and Reeflo) (used)
- 40 watt UV sterilizer (new)
- Two Orphek Atlantiks (used)
- Heater (new)
- Bubble magnus skimmer (used)
- Apex (new)
- Misc pumps

Fish room:
- Reef Octopus pump for water system
- Booster pump (not running when tripped)
- QT pumps, lights, and air pump
- Large fluorescent shop light above QT tanks.

Any tips on tracking down what's causing this?

 

[dwest]

I've been working through setting up a RS650 (see build thread) but I've been having issues with my GFCI outlet randomly tripping that has been pretty frustrating. The strange thing I can't seem to figure out is that it's not consistent. I've spent a fair amount of time searching through articles and forum posts and the suggestions are pretty much all the same: start plugging each piece of equipment one by one and see what trips it. The trouble for me is that the tank will go weeks at a time without issue and then suddenly trip in the middle of the night, so I'm not sure the best way to eliminate the source of the issue one by one. Not surprisingly it seems most likely to trip after an evening that I've tinkered with something.

At first it tripped probably 3 times over the course of about a week and a half, all at night and several days apart. The outlet was a GFCI/AFCI and so I swapped it out for a standard GFCI thinking that the the arc fault was tripping it. I thought it was solved because it went a full two weeks before tripping again a few nights ago. It doesn't appear to be timer (but possible) related but always at night so far.

Last night I removed the "daisy chain" on the outlet so that it only trips for stuff on the tank directly, and a separate outlet for the fish room. I tested with a multimeter for any stray current by placing the common probe into ground and the red probe in the water, no current down to the most sensitive setting on the meter. I also attempted to create a temporary grounding probe (hooking up ground into the water) hoping the outlet more likely to trip consistently, but it didn't. I'll probably end up installing a third GCFI, but I need to get an Apex Energy bar before I do because the power is being fed through a single Apex EB. This would at least mean I could keep my MP40s and pumps on a separate outlet.

I've read that running too many appliances off a single outlet can be problematic, but I can say that I've run tanks with at least as much equipment off a single outlet without troubles. It's currently pulling less than 2amps, which is well under the 15amp outlet. Here's a list of equipment I have running:

Tank:
- Two MP40s (used)
- Two Gyres (used)
- Two return pumps (Reef Octopus and Reeflo) (used)
- 40 watt UV sterilizer (new)
- Two Orphek Atlantiks (used)
- Heater (new)
- Bubble magnus skimmer (used)
- Apex (new)
- Misc pumps

Fish room:
- Reef Octopus pump for water system
- Booster pump (not running when tripped)
- QT pumps, lights, and air pump
- Large fluorescent shop light above QT tanks.

Any tips on tracking down what's causing this?

I was going to suggest replacing the outlet but you’ve already done that. My next suggestion would be to run without the UV and see what happens. I have a 57 watt high end model that seemed to trip my outlet no reason. Hopefully others will respond.

 

[MnFish1]

Is there any possibility that a drop of water is randomly going out of the tank (like a splash, bubble popping, etc) - that is randomly hitting the outlet or a piece of equipment. This was happening in my tank

 

[KStatefan]

I would suspect the ballast from the uv or fluorescent

 

[Sean Clark]

Did this outlet have any prior history of tripping before the tank was set up? GFCI receptacles can be sensitive to radio frequency interference. This could be from your MP40s if you have the wireless chip. Sounds crazy but RFI tripping GFCI is a real thing that happens.

 

[pecan2phat]

I would suspect the ballast from the uv or fluorescent

I'd 2nd KStatefan's suspicion, seen it in my setup also.

 

[theMeat]

Unplug one thing at a time. Being it’s random it will take longer to figure out but don’t see another alternative

 

[littlebeard]

Sounds similar to a situation I had. Was the cheap pump I used for my ATO. I turned things off and on repeatedly until I found the culprit. The pump would only trip the outlet maybe once in 20 times when turned on.

 

[dmsc2fs]

Here is another suggestion, as odd as it may sound. When it trips, go check other things in your house to find if anything else is off. Or switch the main breaker on that line off and do the same.

I had the same problem. GFCI would trip constantly. I struggled to find the cause and once I did It made sense, but was confusing. My tank is in a room that is detached from my kitchen and does not have a shared wall with the kitchen. I have one outlet in my kitchen that is the same line as my tank. That single outlet is the one behind my fridge. 14" to the right of that outlet is a GCFI outlet on a different circuit. You would think the fridge would be on a kitchen circuit? Not in my house. It boggles my mind on why a single outlet for my fridge would be on a circuit that is a breaker for another room.

I solved my problem by moving the fridge plug to the outlet 14" to the right.

 

[nickmealey]

Is there any possibility that a drop of water is randomly going out of the tank (like a splash, bubble popping, etc) - that is randomly hitting the outlet or a piece of equipment. This was happening in my tank

It is possible and has been one of my suspects. I think I'll grab one of those exterior outlet covers to protect against this.

I would suspect the ballast from the uv or fluorescent

The interesting thing is that pretty much every time it's tripped the UV light has been off for hours (it's on a timer). The UV could be it, but it is a brand new unit from Pentair. Also I'm not 100% sure on this, but I'm pretty sure I've had it tripped while the UV wasn't on.

Unplug one thing at a time. Being it’s random it will take longer to figure out but don’t see another alternative

Yeah I'll have to try this. It will take some time but worth it if I can find the issue.

 

[nickmealey]

Update: I ended up splitting up the outlets from the main tank and the fish room. Just before bed tonight it tripped - in the fish room. This makes the florescent shop light a major suspect here considering there's not a whole lot of other equipment running off that outlet and the timer turned off recently. It still could be the UV since that's also plugged in there, but progress nonetheless.