Converting 220v boat to 110v technical advice needed

[Tdh001]

Originally Posted by a64pilot

You use the bigger transformer to change 110 to 220,so the Boat can be run on 220, just like it was made to, no modifying anything.
If you don’t think 5,000 W is enough they go to 15KW for less than $500,but weigh about 100 lbs I think.

The 500 W transformer or smaller is for running individual 110 V things inside of the boat, like if you carry US appliances to Europe, you need a transformer to turn 220 to 110. I had a bunch in Germany, from 50W all the way to 1500W.
Best in my opinion to source 220 V appliances, but transformers work.

Idea of a transformer is you leaving the Boat stock, not charging anything.
I saw a friends Amel Super Maramu that he had changed the wiring on the shorepower plug to make it work on US 110. Only way that can work that I can see is your feeding 110 V into every neutral on the boat, and they are all interconnected and not circuit protected.
I guess it works, but I would have a hard time sleeping at night.

Yes. Sound sleep is important. I’m looking at the Victron Energy Isolation Transformer 2000W 115/230V to put somewhere between the boatside plug and the boat’s circuit breaker.
Still have to get a new plug and shore cable but I figure with the transformer I should not have to make any other modifications ever again (I hope)

[Tdh001]

Originally Posted by windcastle1

Assume you will use 220 volt US power and keep the boat as 230 volt and use small 220 to 110 volt transformers in the boat where ever you need 110 volt? If yes you can use a Victron isolation transformer. They make 3 sizes from 2000, 3600 & 7000 VA

Great advice. I’m looking at the Victron Energy Isolation Transformer 2000W 115/230V now. I think this may be the solution as I intend to take the boat back to the Med next year.

[Cheechako]

Originally Posted by Tdh001

You mean the wires running to the electric outlets?
I read (on the internet) that given how short the distances are (she’s a 44ft sailboat) wire size is not a significant factor.
Is that info incorrect?

That could be correct. Find out your wire size, limit the amperage to what it will carry if you dont want to rewire. It might be fine for say 20 amp service. Make your breaker for 20 amp if so.
A 1500 watt space heater is about 12 amps. That is likely the biggest potential load you may have. But they do tend to overheat a circuit so I wouldn't use that big a heater if you intend to use a heater.
Wire length for determining load capacity is the total length to and from. So if it's a 10 ft length to the outlet, you use 20 foot to calculate.

[a64pilot]

I don't think an isolation transformer will transform power from 110 to 220.
Best verify first before you buy.

In Korea for instance, the houses they Rented to US service members, they would put a largish transformer on the outside of the house that converted 220 to 110, so US soldiers could use everything they brought with them.
Hot water, heater and stove were gas

It's actually a whole lot easier to go from 110 VAC to 220 VAC than it is to go from 12 VDC to 110 VAC, but we do that all the time and think nothing of it.

[Tdh001]

Originally Posted by Cheechako

That could be correct. Find out your wire size, limit the amperage to what it will carry if you dont want to rewire. It might be fine for say 20 amp service. Make your breaker for 20 amp if so.
A 1500 watt space heater is about 12 amps. That is likely the biggest potential load you may have. But they do tend to overheat a circuit so I wouldn't use that big a heater if you intend to use a heater.
Wire length for determining load capacity is the total length to and from. So if it's a 10 ft length to the outlet, you use 20 foot to calculate.

I keep forgetting to look at the wires...
How about one of these:

Won’t a 30a to 15a Adapter like this one do the job or do I still have to worry about the voltage?

Also, my current (2 pole) circuit breaker has a rated operating voltage of 230/400 VAC. Now if I’m serious about protecting the boat’s electrical system in 110v countries, the breaker won’t trip at anything below 400VAC correct? Is this something I ought to be worried about?

[Cheechako]

Originally Posted by Tdh001

I keep forgetting to look at the wires...
How about one of these:Attachment 176666

Won’t a 30a to 15a Adapter like this one do the job or do I still have to worry about the voltage?

Also, my current (2 pole) circuit breaker has a rated operating voltage of 230/400 VAC. Now if I’m serious about protecting the boat’s electrical system in 110v countries, the breaker won’t trip at anything below 400VAC correct? Is this something I ought to be worried about?

All those do is "make it fit physically", they have nothing to do with protection...

[a64pilot]

I wish I had a quarter for every time I saw a Soldier put one of those plug adapters on their Stereo or TV etc. plug it into 220 and immediately fry it.

In all honesty, you can literally get yourself killed and or burn down your boat.
I almost never say this as I believe people can read, study and do most anything, but you need to hire a real Pro electrician, for an hour if nothing else and just ask questions.

[Tdh001]

Originally Posted by a64pilot

I wish I had a quarter for every time I saw a Soldier put one of those plug adapters on their Stereo or TV etc. plug it into 220 and immediately fry it.

In all honesty, you can literally get yourself killed and or burn down your boat.
I almost never say this as I believe people can read, study and do most anything, but you need to hire a real Pro electrician, for an hour if nothing else and just ask questions.

Yeah... you might be right.

[Kenomac]

Lot’s of bad advice on this thread. HIRE AN ELECTRICIAN before you... do anything.