Help: Apex COR 20 randomly tripping GFCI

[theatrus]

So the problem isn't in the power supply? It's in the actual pump itself?

There would generally need to be a path for it to trip the GFCI - this could be through the power supply Y capacitor (unusual especially with a replaced power supply) or through another path (ground probe in the tank?).

All the GFCI is doing is comparing current Line to Neutral. If it goes out any other way for more than a few milliamperes it’s going to trip. This means something is earth referenced in the water in addition to the pump.

 

[Steve Zee]

Theatrus is right regarding the GFCI function. But it doesn’t have to be just a path to ground. General leakage occurs in everything and that means it could be a cumulative leakage of up to 6mA that causes the gfci to trip. Meaning that general leakage can happen on multiple devices and seems to happen with older tanks and salt creep. This may not be the answer you want to hear but something to consider if you can’t find the issue with the pump. And I wish I could count on the times I’ve been called out to a job just to track down a faulty cheap Chinese power supply was the problem.

I personally think everyone should protect their tanks with 20mA or 30mA trip set gfci since the class A code was designed to protect children.