My boat is currently plugged into shore power. If my battery selector switch is turned off and all of my breaker switches are in the off position as well but my reverse polarity A/C main breaker is in the on position (so basically, everything is off except the reverse polarity A/C main breaker), should I still be able to receive power to my A/C outlets? If so, is this dangerous or similar to plugging directly into an A/C outlet?
reverse polarity A/C main breaker
- Thread starter jr22553
- Start date
At least on my boat, there are breakers on the AC portion of my panel that have to be ON to provide power to the AC outlets and the other loads. The AC main breaker has to be on and the individual ac load breaker has to be on. I can't imagine that you'd have an AC outlet powered directly from the AC bus without an isolation breaker for the outlet (unless the installed by the Previous Owner.)
If the breaker is showing reverse polarity, you shouldn't be able to close the AC breaker, and thus no power to AC outlets.
Not sure about the “reverse polarity breaker”, but my boat has separate breakers for 110v outlets (1 for the front, one for the back outlets).:
So, if the main breaker is on, but the out,et breakers are off, no juice to the outlets.
But I treat the outlets as just the same as plugging in at home (but I can trip the breaker if I turn on too many high current gizmos).
Greg
I think this link will answer some of your questions.
You do need to track down the reverse polarity problem. It could be caused by the shore power source or the neutral and hot wires not paired correctly behind your shore power plug on the boat, or the black and white wires are reversed on the boats main ac breaker.
Hunter 27 AC Main breaker DC breakers
Hi new owner to 1979 Hunter 27 and started to go over electric. Previous owner had a fresh water flood while dry docked from a disconnected scupper line and a dead battery. Flood line reached half way up on breaker panel, completely submerged the ac main breaker, battery switch up to DC bilge...
forums.sailboatowners.com
You do need to track down the reverse polarity problem. It could be caused by the shore power source or the neutral and hot wires not paired correctly behind your shore power plug on the boat, or the black and white wires are reversed on the boats main ac breaker.
Thank you. This is what is confusing me which is still getting power from A/C outlet when reverse polarity main A/C switch is on but everything else is off. Here is a picture of what the breaker switch panel looks like. Sorry for the mess.
Attachments
Lets clear some terms. Calling it a "reverse polarity main A/C switch" is confusing the issue and taking the discussion off track. The reverse polarity function does not seem to have anything to do with your question. Lets just call it the Main A/C Power Breaker and see if we can understand the issue.
I think you are saying with the Main A/C Power Breaker on but NO OTHER breakers closed (on) you still have power the A/C outlets - is that correct? Do you have power to the A/C outlets with the Main A/C Power Breaker off and no other breakers closed?
With all load breakers off:
IF power to outlets with main A/C Power Breaker off - then A/C outlets leads are connected upstream of the Main A/C Power Breaker and this is UNSAFE AT ANY SPEED!!!! Your only current overprotection is on the Shore Power stand on the pier. Hopefully that is not the case.
IF power to the outlets with the main A/C Power breaker ON (but not when OFF) - then the A/C outlet leads are connect directly on the outlet side of the main A/C Power breaker OR are connect directly to the A/C bus (downstream of the main A/C Power breaker) and are apparently not protected by a dedicated circuit. In this case your only overcurrent protection is the main A/C Power Breaker. Not and ideal situation and not in accordance with standard wiring practices and probably not in accordance with AYBSC standards.
I think you are saying with the Main A/C Power Breaker on but NO OTHER breakers closed (on) you still have power the A/C outlets - is that correct? Do you have power to the A/C outlets with the Main A/C Power Breaker off and no other breakers closed?
With all load breakers off:
IF power to outlets with main A/C Power Breaker off - then A/C outlets leads are connected upstream of the Main A/C Power Breaker and this is UNSAFE AT ANY SPEED!!!! Your only current overprotection is on the Shore Power stand on the pier. Hopefully that is not the case.
IF power to the outlets with the main A/C Power breaker ON (but not when OFF) - then the A/C outlet leads are connect directly on the outlet side of the main A/C Power breaker OR are connect directly to the A/C bus (downstream of the main A/C Power breaker) and are apparently not protected by a dedicated circuit. In this case your only overcurrent protection is the main A/C Power Breaker. Not and ideal situation and not in accordance with standard wiring practices and probably not in accordance with AYBSC standards.
When I rewired to get the 110 out of the panel for 12V, I added a pilot light wired between the HOT and NEUTRAL leads BEFORE ANY breakers. This light has nothing to do with revers polarity other than it will not light if it IS reversed. AND, when lit, it will tell you there is AC on the shore power cable. A second pilot light is wired between NEUTRAL and GROUND and will light if the supply is reversed, thus putting 110 on the neutral wiring and operating the reversed polarity light..
I'm a little confused by some of your terms but lets set one thing asside. Unless you have an inverter installed in your system, your batteries are not connected to your AC outlets in anyway so the battery selector should have no effect on your AC outlets.
Then you said "all of my breaker switches are in the off positions". Followed by " ...the AC main breaker is in the on position". I'm not sure what you mean by "all of my brekaer switches". If you are referencing the switches that say things like "nav. lights" or "cabin" ... those are all DC and not part of your AC system.
A picture of your electric panel would be helpful.
Your circuit breaker panel is the same as my old one that I removed. There is only one AC circuit breaker. All the others are DC. The AC breaker only powered the AC outlets.
You asked if you can safely use the AC outlets with all the DC breakers off. Yes you can.
You asked if you can safely use the AC outlets with all the DC breakers off. Yes you can.
I admit I was confused by the term "reverse polarity A/C main breaker". I have no idea what that is, but others have guessed. Accurately, I hope.
You sound like you're up for adventures in marine electrical systems, so let's get you up to speed so that you can ask good questions, we can help more effectively, and you stay unelectrocuted.
I strongly recommend you invest some time in the subject before getting in too deep. I found Charlie Wing's book to be a helpful start in my journey. Nigel Calders' Boatowners Mechanical and Electrical Guide is a good resource for a broad range of electrical systems. Don Casey is known for his excellent writing. Then there's Rod Collins at Marinehowto.com and on this forum as Maine Sail, and Stu Jackson's many references here and on other forums. There's a lot of information out there. It has taken some study but has been entirely worth the time. It's an ongoing interest for me now.
Dig in and enjoy learning a new skill!
You sound like you're up for adventures in marine electrical systems, so let's get you up to speed so that you can ask good questions, we can help more effectively, and you stay unelectrocuted.
I strongly recommend you invest some time in the subject before getting in too deep. I found Charlie Wing's book to be a helpful start in my journey. Nigel Calders' Boatowners Mechanical and Electrical Guide is a good resource for a broad range of electrical systems. Don Casey is known for his excellent writing. Then there's Rod Collins at Marinehowto.com and on this forum as Maine Sail, and Stu Jackson's many references here and on other forums. There's a lot of information out there. It has taken some study but has been entirely worth the time. It's an ongoing interest for me now.
Dig in and enjoy learning a new skill!
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The reverse polarity light only indicates the is voltage between the neutral wire and ground. This typically means hot and neutral wires are reversed - in 1) boat inlet 2) the cable or 3) the pedestal. You’ll née a VOM meter to tell where, but since your asking I’m going to assume it will be safer for you to hire a marine electrician to sort it out.
BTW when using small generators on the boat like a Honda 2000 the light will come on even tho the wiring is perfect. This is because they have a floating ground and really are generating +&- 60V.
BTW when using small generators on the boat like a Honda 2000 the light will come on even tho the wiring is perfect. This is because they have a floating ground and really are generating +&- 60V.