Polarity issues ?

[captainmas]

Hello Capts,

I have a 1971 57' Carrie Craft Houseboat we just purchased and are refitting.

We have an issue with the polarity on one side of the boat. We have two 30 amp shorepower systems. The one side works fine, the other side's polarity sensor goes off as you turn on the breakers. All wiring up to the breaker box is ok.

Any thoughts?

Thanks,
Mike Mas

 

[Lyle29464]

Re: Polarity issues ?

most boats in 71 had the same setup you might have. That is 2 110v 30 amp setups, same leg. (NOT set up for 220)

I am guessing your dock side power is 220 or the 2 legs that go to your boat are different.

second guess is you really do have a 220 setup on the boat and you have just split the 110 from the dock. So you have the same phase.

 

[captainmas]

Re: Polarity issues ?

No it is not 220 on ether side dock or boat, two seprate leads/plugs both 30 amp one side works the other does not, also the same thing at differant docks shorepower. one side works perfect the other sides polarity sensor alarm goes off when you flip on any of the breakers that have a draw on them or if you turn on the applaince, breakers do not pop and we have checked the polarity into the breaker box and its ok. It seems like it is in the box as all the breakers do the same thing when there is a draw placed on them.

 

[seabob4]

Re: Polarity issues ?

Mike,
Have you checked the branch circuits for incorrect wiring at any outlet or directly into an appliance? The way I wired my panels at Stamas was that certain branches ran off shore 1, the others off shore 2. So I'm guessing the faulty wiring is in one of the branches off the 30A breaker that is showing the polarity fault...

 

[captainmas]

Re: Polarity issues ?

SeaBob,

Thanks for the reply, I just spoke to the past owner who had the boat for the past 30yrs, he said that he had this problem over the last couple years at a couple docks, that it was intermitent at first than just went away. At this point all the breakers are effected on the one side. He also said he had a problem with the other side a few years ago and replaced a bad breaker and it solved the problem.

Can a ground fault in one appliance effect the whole side? And what would be the best way to find the bad one?

Thanks Again,
Mike

 

[captainmas]

Re: Polarity issues ?

One other thing I just noticed, The green lead going into the breaker panel connected to the DC ground buzz bar on the good side is a solid ground wire, the green lead coming into the panel on the bad side is solid and spliced into a large gauge {looks like a 10 G} multi strand wire into the DC ground buzz bar, is it possable the spliced wire is causing the problem and some how kicking the polarity sensor off?

 

[seabob4]

Re: Polarity issues ?

Think about this. Shore Power inlet to panel. Hot and neutral to 30A breaker, neutral jumped to neutral bus, ground straight to ground bus. All grounds from downstream appliances to ground bus, all neutrals to neutral bus, all hots to respective breakers...

Somewhere a hot and neutral are reversed, and since neutral is common throughout...hence, one device can show reverse polarity on the entire circuit...

 

[captainmas]

Re: Polarity issues ?

Very Good, I think your right......The guy who owed the boat before was a do it yourselfer...with his son and son inlaw as helpers...I'll ck and see what they installed, very possable they crossed something or grounded something by landlubbers standards, IE grounded the white and green together, which correct me if I'm wrong, would also kick the polarity sensor and short the system.

Also most of the house wiring looks like it's just that "house wirng" it is orginal from 1971, so it's quite possable that a non marine electrician installed or fixed something.

Last looks like everthing is missed label on the panel box, wiring was not switched from side to side, but the working side runs the stuff labeled on the non working side.

The hunt for a short/crossed wires will begin. Any ideas on how to ck for the short or crossed wires from the breaker box?

Thanks for your help.
Mike

 

[seabob4]

Re: Polarity issues ?

First step would be to check continuity between the ground and N buses at the panel. There should be no continuity. If there is, then the scenario you described of grounding the N to ground would be true somewhere.

If no continuity is found, the next thing I would do is check each outlet's hot prong (the small slot) with the hot on the outlet breaker (load side of the breaker). If a N and a hot are reversed on one of the outlets, then that will show as an open on one of the outlets.

If nothing is found doing that, then the problem would lie with one of the appliances on that branch that is wired directly to it's respective breaker. In this case, you'll probably have to start pulling appliances to inspect the wiring on the back side...

 

[captainmas]

Re: Polarity issues ?

Thanks, I have an electrician buddy coming over tonight. I will let you know the out come.

 

[captainmas]

Re: Polarity issues ?

Just as an update, still hunting it down, did not finish, will keep you guys posted.

Have a Merry Christmas and Great New Year !

Thanks Again,

Mike Mas

 

[seabob4]

Re: Polarity issues ?

To your family as well!

Keep us posted on the TS outcome...

 

[captainmas]

Re: Polarity issues ?

Have a great New Year, we got nailed with the blizzard and I hope to be able to get to the boat in the next few days.