reverse polarity

[spartan]

I just had a boat surveyed and he said that the generator had reversed polarity.
Is the fix as easy as swapping a couple of wires or is it a big job ?

 

[FF]

Should be easy as >swapping a couple of wires,<

However I would get a second opinion to weather it is actually reversed ,as it is hard to contemplate reverse polarity on board for a long time.

You may have used an idiot surveyor

 

[Scary]

Good point

Should be easy as >swapping a couple of wires,<

However I would get a second opinion to weather it is actually reversed ,as it is hard to contemplate reverse polarity on board for a long time.

You may have used an idiot surveyor

Some of the older Chinese boats used red and black ac wiring. Black was the neutral red the load. l have seen black to black connections shore power to ship effectively reversing polarity of the whole boat. I can see that happen on a generator installation as well.

 

[rwidman]

I doubt it's a "big job", but I don't think it's a DIY job if you had to ask on a web forum. Electricity can be dangerous on a boat if not done correctly. My suggestion is to bring in a qualified marine electrician to determine if you actually have a problem and to fix it if you do. You'll sleep better at night.

 

[Xsbank]

If you are a boat owner, paying someone to fix your problem is ok if you can afford it, but I maintain that ignorance is more dangerous than electricity, so you need to get in there (power off) and learn how your system works!

 

[psneeld]

Asking web forums are exactly what they are for...once the info is reviewed...then people can make up their own mind to proceed, keep investigating or take it to a pro.

Going out on a boat is dangerous to a degree....yet we have a forum of DIYers as very few here take command of their boat without 30 years of professional/certified experience.

Almost all reverse polarity problems are easily solved...not easily found....so a simple question and a few simple..."no it shouldn't be too big...just make sure you recognize and think though the issue" might be just the right encouragement for him to press on...DIY until he recognizes he is in over his head (or not)...

 

[RT Firefly]

Greetings,
Mr. s. Welcome aboard. As Mr. X mentioned POWER OFF! I might add, IF you have an inverter on board make sure it is OFF as well.

 

[obthomas]

Swapping wires is no big deal. Where you swap them may be a problem. Lets suppose that the generator is wired backwards yet the overcurrent is wired correctly. If you swap the wires after the over current protection then the polarity is right but the over current protection is wrong. Know what you are doing or any way you do it will likely be wrong.

 

[rwidman]

If you are a boat owner, paying someone to fix your problem is ok if you can afford it, but I maintain that ignorance is more dangerous than electricity, so you need to get in there (power off) and learn how your system works!

You can "get in there (power off) and learn how your system works!" all you want to but unlike water or lumber, you can't see were the electricity is going. If you want to learn electricity you need to go to school or at least be very good at learning from books.

Just staring at a bunch of wires won't tell you anything and there are ways to connect things so they work fine but are very dangerous.

 

[Ski in NC]

Gennies need the neut lead grounded in the box. Often they are shipped with no such connection made. A tech then wires up the output with the neut ungrounded, causing volts to "float". A test with a meter will confirm. Who ever sorts this NEEDS to know what they are doing.

 

[Andy G]

All of the above, and check your life insurance is up to date.

 

[psneeld]

Harry Callahan: A man's GOT to know his limitations.

Good advice....for anyone, anytime.

But there are certainly electrical projects (and other than electrical) that are pretty straight forward and a simple wiring diagram and connector info (such as torquing certain connections) is within many handy person's capabilities....

You don't have to be up on theory to be an installer as long as someone else (such as a manufacturer's wiring diagram) has done the homework.

The best part of forums is when you gat the cross section of advice...

1. The "don't do it" crowd
2. The "even a caveman can do it" crowd
3. The truly helpful "post links and pictures and adequately describe what pitfalls may be encountered" crowd so Harry Callahan and friends can use their own brain and risk tolerance to see what they want to take on.

 

[Rogerh]

Psneeld, you hit it right on...... True for so many of the post on here.

 

[ancora]

When we bought our 36' Nova it had no gen set so we bought one at a boat show and I installed it. Everything went well until I tried to get the gen set to feed the boat panel. As the Taiwanese do not believe in color coding wires it was touch and go until I found the right hookup. That was 14 years ago and the thing is still runnin'.

 

[FF]

>As the Taiwanese do not believe in color coding wires<

The early Tiawanese did nor believe in color coding as many cable runs were made up of lengths of wire spliced end to end .