These things are not rocket science. It's just a light and a resistor between the neutral and ground. Failure modes are loose connections and short circuits. False negatives are more likely than false positives. Still it can happen. More likely is bad wiring on the boat side than a failed indicator. Most likely is bad wiring on shore.I've wondered about this. How do you check this function? Mine has never shown a reverse polarity, but who knows what that shows?
Hmmm. I don't think I'd want to stay at that marina. It's actually a serious matter. As in, could kill somebody. Pick up a receptacle tester for a few bucksI got a reverse polarity indicator light go on when I plugged in at the marina. Unplugged from "our" outlet on the pedestal, and plugged into our neighbors outlets on the same pedestal and got no alarm. Plugged in to outlets on the pedestal for the slip across the dock, and got no alarm. Reported it to the dockmaster, and was told "We'll get around to it, go ahead and plug in across the dock."
The problem is this doesn't determine whether the problem is the boat or the dock wiring.Hmmm. I don't think I'd want to stay at that marina. It's actually a serious matter. As in, could kill somebody. Pick up a receptacle tester for a few bucks
Just plug it in, it can show reversed polarity, open hot, open neutral, open ground. For a few bucks more you can get one that you can use to test GFCI receptacles.
Those testers are not twist-lock and will not plug into a proper shore power receptacle. They can only be used to check the outlets on the boat.Doesn't show dockOR boat??
Mebbe it does? Seem a ta me that ya;
Unplug boat.plug tester into pylon. check idjit lites. . bad? yanno it's there.. If good; plug in boat and check recept on boat.