jfuller8400 Posted November 22, 2020 Share Posted November 22, 2020 So for the past couple of years I've been having issues with one of my power feeds constantly tripping its GFI. I spent hours of troubleshooting trying to isolate the problem controller, all without success. Everything would be fine when I ran my test sequences but the circuit would trip at random points during a show. This year during the show setup and testing the GFI started to trip immediately (hurray - I can finally repeat it on a regular basis). During troubleshooting/isolation procedures I found that the trip was being caused by a power supply for one of my CMB24D controllers. So I thought, hmm... the PS must be going bad. Not to worry - I had a spare. Swapped the PS out and.... the GFI still tripped. Ok, I thought - let's trying moving that controller to a different circuit/GFI. Did that and the controller ran fine and did not trip the GFI on the new circuit. I've heard that some GFI devices are more sensitive than others, so I just reconfigured the power feeds for that one controller to move it to another circuit. Fired up the show and after a few seconds, the first GFI tripped again. #%*@$!*~!!! That's when I remembered I had two other CMB24D controllers with similar PS on that circuit. Reconfigured their power feeds as well and voila - no more GFI trips! So I can only assume there's something with the PS I'm using and that one particular GFI. It would be interesting to know if a better class of PS (like a Meanwell) would still cause the GFI trips or if it's just a finicky GFI. At any rate I just wanted to share. Link to comment Share on other sites More sharing options...
TheDucks Posted November 22, 2020 Share Posted November 22, 2020 Are these GFCI or AFCI breakers/outlets? Inside (sheltered) or outside? There may be moisture and dust inside the junction box (a combination the causes leakage current to rise). And these device do go bad with age and higher trip counts. And What brand of PSU do you have? (not to blame a vendor, but to see if there are Me Too's) Link to comment Share on other sites More sharing options...
k6ccc Posted November 22, 2020 Share Posted November 22, 2020 Yea, it could be the crappy design of the power supply. Leaking current is additive, so one power supply that has 3mA of leakage won't (or shouldn't) trip a GFCI. But add a couple more of the same ones and now you have 9mA of leakage which will (or at least should) trip a GFCI. The problem is that if the power supply has input capacitors between hot, and neutral to ground, there will be a small leakage that will be seen by a GFCI. One power supply is not normally a problem, but multiple can be. This is the same issue with standard light strings wrapped around metal tomato cages for mini trees. Every time the wire wraps around the metal, there is a tiny capacitor created. Each one is leaking a tiny amount of current, but there are hundreds of those in every mini tree. It adds up. Link to comment Share on other sites More sharing options...
Orville Posted November 23, 2020 Share Posted November 23, 2020 Sometimes it's just the GFCI went bad, it happens. I am going to have to replace my outside GFCI with a new one because it's old and started tripping for apparently no reason at all. At least I couldn't find any issues anywhere. Borrowed a GFCI from inside the house, connected to the outdoor junction box, tested and everything worked fine. So I know I've got a bad GFCI that must be replaced, and I just replaced this one just a little over 2 years ago and it's already gone bad! I've had others work for many years {5+} without issue, but finally needed replacing going on their 6th/7th year of use. And the replacement was identical to the one that lasted 5+ years. /\/\akes me think they aren't building GFCI's like they used to, not when one goes bad in or just a little over 2 years! Link to comment Share on other sites More sharing options...
jfuller8400 Posted November 23, 2020 Author Share Posted November 23, 2020 20 hours ago, TheDucks said: Are these GFCI or AFCI breakers/outlets? Inside (sheltered) or outside? There may be moisture and dust inside the junction box (a combination the causes leakage current to rise). And these device do go bad with age and higher trip counts. And What brand of PSU do you have? (not to blame a vendor, but to see if there are Me Too's) So this is a GFCI outlet in an enclosure outside on the side of the house. I replaced it a couple of years ago after the old one fried (long story involving hornets and spray killer 😁). So it could be this specific unit. In terms of PSU's, I don't know the brand as they are just ones I got off Ebay. So I could easily believe they would be the source of the problem too. Just interesting that they don't trip the other (read older) GFCI's that I have. Link to comment Share on other sites More sharing options...
TheDucks Posted November 23, 2020 Share Posted November 23, 2020 I just joined having this issue last night. 🥺 Why no lights, they were working when I changed a AC string out (way too dim) for another DUMB RGB one (connected to a nearby CMB24). All the controllers on that one have been powered for days. This GFCI is new (I upgraded the garage outlets that had NO GFCI) less than 6 Months ago. Link to comment Share on other sites More sharing options...
k6ccc Posted November 23, 2020 Share Posted November 23, 2020 Welcome to the club. Fortunately the only time I have had a GFCI trip was 100% legit. I have a bunch of equipment inside two brick columns. In a rain, I got a water leak that dripped some water onto one the common Chinese 350 watt 12 volt power supplies. Killed the power supply, but there ended up enough leakage current that it tripped the GFCI that was feeding it. Likely protected the power supply from more damage (such as catching fire). Link to comment Share on other sites More sharing options...
TheDucks Posted November 23, 2020 Share Posted November 23, 2020 I split things up a bit to different GFCI outlets. We will see which one trips. Note: this is not an immediate trip. the sequence runs a few hours. BTW It is way too dry (I checked inside boxes) Link to comment Share on other sites More sharing options...
Dr_Aplet Posted November 28, 2020 Share Posted November 28, 2020 Hey All, Here is a strange one... I have 2 little sheds run off an extension cord plugged into a GFCI. One has a deep freezer in it. We have had no problems until I put my controller up. This GFCI IS NOT connected to the controller it ran fine all last night and all day (i left a light on so i could see if its off) my show started at 5:30 its now 7:00 and the GFCI is tripped. Is it possible that all these lights could be sending stray leakage back and being detected by the GFI in reverse? My show is run on a 220v 50amp RV breaker to a job-site power box. Could there be a particular sequence that creates this leakage. i have lights hung on a wire fence but i have not wound anything like a coil. perhaps driving a ground rod in by at my display could eliminate leakage. Any Ideas? Link to comment Share on other sites More sharing options...
k6ccc Posted November 28, 2020 Share Posted November 28, 2020 Not likely, but you likely came up with the issue. A lot of jobsite power boxes are not wired right. The big issue is common neutrals or neutrals tied to each other or ground downstream of the GFCI - ya can't do that. Link to comment Share on other sites More sharing options...
TheDucks Posted November 28, 2020 Share Posted November 28, 2020 My trip turned out to be caused by the CAT$%^& cable confusing the last controller (A Gen3 CTB16PC). As best I can guess without a O-Scope, it causes random sub-second flashes on the 3 prior CMB24, which disturbed the 3 @ 12VPSU just enough to dump the hash onto the Earth lead (green ground) . NB whatever went on with that cable, was so bad that the Controller could not be discovered if I put a 120 ohm termination on it. The cable passed on my CAT5 wiring tester Link to comment Share on other sites More sharing options...
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