240 v conversion to 120v

[AiniA]

I am considering the purchase of a European boat for use in the US. I have two questions at this stage.

1. I know the wiring will not be of adequate size. How hard is it run new wire? Does this depend on make of boat whether it uses conduits or not? I guess I am asking if there is more needed than just fishing new wire.

2. In addition the shore power receptacle will have to be changed. Are the breakers dual voltage or do they need to be changed as well? I assume any battery charger or inverter would need to be changed.

OK, three questions, anything else I am missing? BTW, the boat is relatively new, from a good yard (Finngulf), around 10 metres so not a complicated AC system.

Thanks

[Jim Cate]

If you don't anticipate big AC loads, you might simply leave the wiring as is. The circuit breakers are sized to limit current to a safe level for the existing wiring. I believe that most breakers will work on either voltage... need to check that out for the specific ones installed in your boat.

If larger loads are involved, changing both the wire and the breakers will be needed. The difficulty of pulling the old out and the new in varies wildly between boats. If the conduits are well designed and sized, it shouldn't be too hard. Sadly, those conditions are not that commonly found, so it could be a real bitch to do. And of course changing all the sockets to American standards will be needed in any case.

I expect that all the professional electricians will chime in with rules and regs, and you should listen to them if insurance will be required. You don't want to give them an easy out if a claim is made.

Jim

[westwinds]

The fuse is there to protect the wiring from getting too hot. Determine existing wire size, then amps it can carry, and finally add up the amps for the items the the wire feeds from each fuse or circuit breaker. Do an inventory of electrical items and watts needed for all circuit breakers or fuses. You should also do checks for voltage drops.

[rwidman]

A simpler and possibly less expensive solution is to purchase a transformer (made for this purpose) and install it on your boat (this would be a good job for a pro). Everything on your boat remains 240 volts but the transformer steps up the 120 volts you find in the USA to 240 volts.

Problem solved.

[dfelsent]

As mentioned before, wire gauge is a potential issue.
The breakers may not meet the trip and ground fault requirements even after a re-wire.
The ease of re-wiring is as previously mentioned all over the place.
The charger if you are very lucky will be a 50/60 hz dual voltage unit. The wiring will still need upgrading.
The inverter, if any, will need replacement.
The outlets will need replacement as well. There may or may not be room for an enclosure behind the new outlets.

A second issue is the EPA certification of the engine. There are Euro engine installations that meet the EPA labeling requirements as well as the emission requirements. There are some that do not. The age of the boat and engine factor into the need for EPA compliance.

There are ports of entry into the US that care a lot about this. There are ports of entry that just don't care.

If you are planning on shipping the boat, the shipping company will use a customs broker on each end, as well as a port agent. The US based customs broker for your port of entry will have experience with the EPA issues.

I bought a boat from Scotland this past April. I was fortunate that my port of entry did not care about EPA. I was also fortunate that the engine was properly labelled for the US EPA standards, so if they had cared I would have been fine.

I left the main inverter and the battery charger with the previous owner. I kept the small 220V inverter so I could charge cell phones. Most cell phone chargers are 120/220 V 50/60 Hz.

The boat, though re-wired in Scotland, has 2.5mm2 wire. Slightly over 14 GA. Overkill for 220 but

I have not yet finished the rewire to 120V. That will happen eventually.

The entire process of buying a boat abroad, sailing it there, and importing is was a blast. Lots of logistics.

Oh, and pay attention to bank fees for overseas transfers. there are a few companies such as Transferwise that have much lower fees. It is always scary wiring money into the ether though.

[westwinds]

Originally Posted by rwidman

A simpler and possibly less expensive solution is to purchase a transformer (made for this purpose) and install it on your boat (this would be a good job for a pro). Everything on your boat remains 240 volts but the transformer steps up the 120 volts you find in the USA to 240 volts.

Problem solved.

Isolation transformer:
Marine: Isolation and Boosting Transformers

[travellerw]

Look very closely.. I thought the same.. however after purchasing my boat I found out the wire was not only adequate, it was actually oversize for 120V.. Some manufacturers pull ONE wire size, no matter where the boat will be delivered.

We simply replaced the breakers, added a jumper to the generator and BOOM had a 120V boat (all the devices including the batt charger took both voltages).

[robert sailor]

If your planning on cruising in the future you may just want to leave it as 220v as most of the world operates on this superior system. We have a transformer as well as 120 inverters and a large 220v inverter. Any place works just fine for us. Most new battery chargers work on either 120/220v so that's usually the biggy. Enjoy your new boat!