Silly shore power question

brianflhrci

I've got a 2003 FV 290 and it's my first modern cruising boat.  My question is do I need to turn off the shorepower breaker when I unplug and take a ride?  Also, I don't have a generator, will my fridge run on the house battery?..or what do I do to make this work?

Thanks,

Brian

Lifes Good

Hi Brian

Its good practice to turn off the power before unplugging or plugging in your power cord. Most likely nothing will happen however there is a chance of the power arching and causing damage or electrical shock if you are wet. The refer will switch to 12v automatically.

LG

brianflhrci

Thanks, I'd rather do things right!

gslpro

Brian.  not sure which breaker you are talking about.  LG mentioned turning off the shore power breaker, which is the one one the dock for the cord.  I don't know of anyone who does this, though he is right in saying that there is a possibility of arching.  I did buy an endcap from west marine that screws on to the end of the shore power cable when unplugged from the boat.  It is essentially waterproof, which would be my greatest fear in leaving a line which i hot unplugged.  If it rained enough, and the cord was on the dock, it could cause an electrified puddle, which in that case I would absolutely flip the breaker off at the power pole.  Ounce of safety for sure.

The other breaker, which I believe you were referring to is the one inside the boat.  And no, you need not do anything with that breaker on the main panel.  Everything will run fine on 12v that is supposed to.  The only time you would flip that is if you were going to generator, or for some reason, you wanted to kill 110v to the boat.  For normal operation, leave it on, and just unplug the cordset.  Enjoy.  

Mother Nature is keeping me of my 290 until Friday.  Something about T-Storms that tell me to stay at home.  

brianflhrci

Same forecast here, the weekend looks good though!  unfortunately We don't have breakers at the plug, just at the end of the dock locked up. 

Dream_Inn

I tend to disagree with Gary on the main breaker inside the boat.  I have always turned that off before removing my power cords.  If you don't, at some point you will get arcing because you are drawing power while pulling the cord.  (similar to pulling the power cord on a toaster oven while it is on)  For dock power, I don't always flip the breaker off, but I do try to remember when we leave for extended periods.  FWIW, I've had my own power cord fall in the water hot and not throw the breaker.

TikiHut2

Hey brian, I'd say the shore power question's a good one and I'm sure there's a few varying opinions.

legally (in most places) a means of disconnect can be interpreted as simply locating an outlet with a plug at certain equipment (from toasters to bare bones dock layouts). A cord with a plug is one thing, a switch is even better, a breaker is better yet. It's always a good thing to eliminate the load before disconnecting either end of a shore power cord. Accumulated carbon build up at a plug from a load spark will eventually become an issue but the larger concern on a boat is any chance of ignition of combustible fumes so use of a switch/breaker to remove the load is a good habit.

 Personally I'd try to eliminate the chance of a load by turning off the breaker in the dock box (if there is one) I also then switch off the shore power breaker on the boats electrical panel and then unplug the cord on both ends. ... at least that's my procedure.

Have a safe season, Mike

MarkB

I always switch off the individual 110 V breakers (fridge, charger, etc.) then the main 110 V breaker, the the shore power breaker, then the shore power switch to off before I unplug the main to the dock and finally the cable into the boat.

This avoids a surge during disconnect damaging any equipment. Also you have to make sure that shore power cable doesn't damage anything if it is accidently dropped in the water. So that is why you isolate everything inside the boat first and then unplug at the dock.  If it drops, technically everything is isolated. If you unplug the boat first and drop it in you have a 110 V surge into the water (galvanic damage).

 

brianflhrci

Great info guys!  The Admiral and I are having a great time learning and using the new boat and this forum has been great.

gslpro

I would have to agree with just about everything said here.  I guess I can see the argument about carbon build-up on the plug from the arching.  It makes sense.  I will have to give it some thought.  It is inconvenient to get to the breaker, but for safety-sake, I guess a little inconvenience isn't all that difficult to get over.  For me, if I am going to turn anything off, it would be the dockside breaker.  

I am SO glad to have my "Rinker Forum" back!!

Michael T

It takes 1/3 of the power to run a 40 watt bulb to instantly kill a human being if they are in a wet environment. there is enough power in a 30 amp cord to kill a village. These things are not toys. they are not mickey mouse extension cords. They carry an awesome power punch. From a legal standpoint if you leave your shore power cord connected to a dock outlet and leave the site you are liable for any damages or injuries that result. Flipping the dockside breaker will not absolve your liabiltiy exposure. You must disconnect the end so that your cord is not energized. I disconnect mine, roll it up and place it in the transom storage locker in a waterproof bag. One of the biggest boats in our marina is owned by a lawyer - he unplugs his. I have had two small sunbrella bags made to cover the ends on the Marinco EEl cords that I have. While I'm at it, if you loop a too long shore power cord you are creating a magnetic field causing a heat build-up that can drop your line voltage which causes more heating and so on. Use a shorter cord. Voltage drops will damage compressors and electrical motors. All of the above said, letting shore power cords lie in the water (like 20% of the boat owners at our marina do) further increases risks to others of electrocution, damage to the metal parts of others' boats,damages the coverings of the cords themselves and if the cord is plugged in while in the water - the electricity coursing through the cord will actually try to draw water into the cord. This is electrical 101 stuff. Right length, unplug it when away and keep it out of the water - or - that lawyer in my marina will have an even biger boat next year! There is a great article in Boating Magazine by Mike Telleria (Mikeis an ABYC Master Technician and Certified Syatems Engineer) about marina electrocutions and shore power cords - I think it's worth a look.