120v to 220v

[majinoo]

Hi ,
I am looking at a boat in St Martin but I just saw that a 12/220v electrical circuit , but if I buy this boat, id like to bring it to the United States .
What could I do to solve this problem ?

Thanks

[prae]

Does the boat have a 230V generator or inverter?
Wire a separate 110V system in the boat.Leave the 230 alone.
Obtain a 110V generator for your separate 110V circuit and/or use a inverter/charger for your 110 from the batteries and if you put the 110v generator in, you can charge the batteries.
Check your countries wiring code to see if you can use the same wiring and change the fittings to 110V. Different countries require different colors/insulation for the cable.

[Meridian]

Someone may wish to correct this, but it *should* be a fairly simple matter for a good marine electrician to re-wire you for 110 volt.
Caveats...Wiring may need to be up-sized, inverter/ charger system (if present) may need to be replaced, and any 220 volt appliances/tools etc will need to be replaced with 110 v equivalents.
The wiring upgrade, and a new inv/ charger, could be big-ticket items. Perhaps, in this buyers' market, you could negotiate a price reduction to reflect these anticipated costs.
HIH,
John

[David M]

You wont necessarily have to change the wire gauge, just realize that by halving the voltage you can only carry half the power now. Its rare when an outlet needs to power 15 amps times 120 volts = 1800 watts. How often are you going to need to power something over 900 watts? Perhaps just instal a few outlets for powering things over 900 watts rather than rewiring your entire AC system?

[DeepFrz]

You will definitely need to replace the wiring if you decide to use 110 volts. The wiring in the boat is only good for 1/2 the rated amps of a 110 volt cct. To trust that you will never overload the cct. is just asking for trouble, spelled fire. Many appliances will use more than the 750 watts that the 220 volt wiring will handle. I doubt that any electrician would change the plugs from 220 volt to 120 volt, and neither should you. Advice to the contrary is just plain dangerous.

[GordMay]

It takes power (energy) to perform work.
Power is measured in Watts, where:
Watts = Volts x Amps
Which can be transposed to:
Amps = Watts ÷ Volts
Wire is sized according to it’s maximum Amperage capacity.
Ie:
1,000 Watts @ 220Volt will draw 4.54 Amps
1,000 Watts @ 120V will draw 9.33 Amps (roughly twice the current, and twice the required wire size)

[prae]

Good explanation GordMay. .

[CharlieJ]

Just as important as the power/wire size issue is the line frequency. If this is a foreign made boat, it is very likely that all of its A.C. rotating equipment is 50Hz. Equipment designed for 230 VAC/50 Hz will not run well on 230 VAC/60 Hz available in the USA.
If this is the case, there is no inexpensive way to overcome this issue. You would have to replace all of the vessel's A.C. rotating equipment or install a $15k shore power conditioner.

[MarkJ]

If this guy is buying from St Martin it could be from a well known French factory.

To make production cheaper the whole wiring grid is laid down early in one piece including all the options, wether or not those options have been ordered.

Wouldn't thins grid be cheaper if it were all standard at the highest voltage that could be optioned?

IE It may well be a 240 volt boat, but the compnay may find it cheaper to put in the heavier wiring anyway?

The wiring should be checked before ripping it all out?




Mark

[captjohn360]

funny you should mention it i just went through the same prob. i ended up wireing a parelell 110 circut so i could use 440 when in europe.just switch incomeing shore power. my charger and inverter have a 110 240 switch,look at your msnual. the only thing i couldent switch is the water heater i installed a instant propane heater thats more efficent....jt

[majinoo]

Originally Posted by MarkJ

If this guy is buying from St Martin it could be from a well known French factory.

To make production cheaper the whole wiring grid is laid down early in one piece including all the options, wether or not those options have been ordered.

Wouldn't thins grid be cheaper if it were all standard at the highest voltage that could be optioned?

IE It may well be a 240 volt boat, but the compnay may find it cheaper to put in the heavier wiring anyway?

The wiring should be checked before ripping it all out?




Mark

Hi , its a Jeanneau .
Thanks for the answers and keep them coming !

[DeepFrz]

Many appliances will use more than the 750 watts that the 220 volt wiring will handle.

Oops, a senior moment...;-)

[chala]

“it is very likely that all of its A.C. rotating equipment is 50Hz. Equipment designed for 230 VAC/50 Hz will not run well on 230 VAC/60 Hz available in the USA.”

50Hz rotating equipment will rev faster on 60Hz and 50Hz equipment magnetic core is suitable for 60Hz.
60Hz rotating equipment will rev slower on 50Hz and 60Hz equipment magnetic core is not suitable for 50Hz.

It could be useful to read the following thread: Isolation Transformers
Quote from s/v JEDI post 54
(But the higher the freq., the smaller the components to convert voltage.)

[David M]

Originally Posted by DeepFrz

You will definitely need to replace the wiring if you decide to use 110 volts. The wiring in the boat is only good for 1/2 the rated amps of a 110 volt cct. To trust that you will never overload the cct. is just asking for trouble, spelled fire. Many appliances will use more than the 750 watts that the 220 volt wiring will handle. I doubt that any electrician would change the plugs from 220 volt to 120 volt, and neither should you. Advice to the contrary is just plain dangerous.

With respect to changing the voltage of a 220 volt system to a 120 volt system...

Breakers are gauged to the ampacity of the wire which is directly proportional to the cross sectional area or gauge of the wire (the run on a typical yacht is insignificant for AC). The real problem is not starting fires, the problem is you will be popping breakers if you plug in something that draws more than 900 watts. And on a boat how often is that going to be? My other suggestion of running a few larger gauge circuits such as 14 AWG for a 15 amp circuit at 120 volts is a legitimate way of creating a few 120VAC/15 amp circuits without having to go through the big expense of having to rewire your entire electrical system. I was never suggesting overloading an electrical circuit without correct breakers for the current being drawn. If you re-read my original post I was suggesting leaving most of the AC wire as is and learn to live with half the power being available except for a few circuits that the owner install if he needs to draw more than 900 watts. In my opinion this is a safe, less expensive and viable option to replacing your entire AC system with larger gauge wire.