Both shore power circuit breakers went bad?

[dsolo]

Hooked up to shore power and had 110 v for a very brief moment. Now both breaker at shore power input bad? Turned off panel breakers to isolate power input and checked power cables, breakers. Breakers pass continuity check. But will not pass 110v. Breakers have no positive set. They have no resistance when throwing them on. What would cause this?? I have no ideas!

[bud37]

Try this , you may have but.........shut down all 120 volts ac aboard boat , disconnect shore cables from the boat, check for power at the dock.....then try to reset each breaker at the shore power inlet, before you reconnect shore cords....

[dsolo]

Thanks for the advice. I tried the procedure several times. No luck.

[mjk1040]

Well the moisture over time in that cabinet could have weakened them. Bet they were fun to get out and change in that cabinet. Could the gennset switch over failed and not switched back to shore input? Hope new one solve the problem for you.

[dsolo]

That could be the case. I had a tech working on the generator today. It is running and stopping quickly. He has a tech call into the tech support with the manufacturer.

[bud37]

Source of the post That could be the case. I had a tech working on the generator today. It is running and stopping quickly. He has a tech call into the tech support with the manufacturer.

Well theres your problem, It was hard to believe both breakers would go bad at the same time.........open the breaker on the gen. itself and see if you can power up then.

[mjk1040]

If the genset switch is the cause for a back feed, breakers may be toast. Or the switch not going back may cause a dead short or amp draw greater than the 30 amp shore cord breakers could handle. ??

[tomschauer]

If the genny back fed it should have toasted the breakers in the panel and not the ones at the shore power inlet.
It sounds like you have made certain you have 110 at the boat end of the cords and the wiring from the inlet plugs to the breakers are good?

[dsolo]

Correct, I checked the voltage at the shore input and it had 120 vac. I then checked the breaker with a continuity tester and got continuity through the breaker. I connected the shore power and got 120 vac on the breaker input terminals. With breaker on there is no voltage at the breaker output.

Guys I need to know how these breakers fried? I don't want to replace them to only fry another batch.

I am in Leland township harbor. I discovered the toasted breakers here after connecting the shore power. I saw 120vac at the panel for a short time. It then went to zero voltage. The dock attendant stated the shore power I plugged into did not work? He switched the power source to a nearby terminal. It is the terminal I verified had 120 volts at the boat.

So I have two possibilities, Genny back feed, witch I eliminated the circuit by turning the generator breaker off. Made no difference.

Now, how could a bad voltage at the shore power terminal fry the boat breakers?

Dan

[tomschauer]

that's a tough one. Even if they screwed up and hooked you to the high leg of a delta system (about 170v) it shouldn't have toasted your breakers. It would have toasted everything else on the boat in fairly short order but not the breakers.