240v to 110v Transformer for USA Boat

[chinita]

Often wondered about the complications of having a USA spec boat with 110v shorepower system. I have seen them with yellow box transformers in the cockpit but is this a long term solution for a permanent import?

Comments and experience appreciated. What works/does not work? Any regrets?

TIA

 

[Norman_E]

Best starting point would be to list all the 110 volt mains appliances and check whether any are dual voltage, and then decide whether it is cost effective to replace all the 110 volt equipment with 220-240 volt kit. If not then you need professional advice on a permanently installed transformer rather than one sitting in the cockpit.

 

[rustybarge]

Just plug straight into the uk mains.......USA cables are twice The thickness because of the lower voltage. Convert the sockets to uk spec.
Fuses will be a higher amperage, just install a smaller main fuse, the rest will be ok.

You will need a simple step down transformer for USA inverters.

Maplin will have a suitable transformer 110/240 ac

Converting from uk voltage to USA would not be possible, a total rewire is necessary.

 

[Jabs]

You also need to consider the issue of frequency.

Anything with a motor will run 20% slower and consume more current.

Fridges and air con may not be as efficient.

Tony.

 

[stearman65]

US 110v

Is a different frequency to UK or European 220/240 voltage, one is 50 cycles the other 60 cycles, so beware, you could fry the US items with a transformer, you also need a converter which is a massive cost I believe.
Stearman65.

 

[chinita]

Thanks to all so far.

So,

The yellow box I have seen on USA boats has a 240v shorepower lead and plug going in to it on one side and a 110v plug and cable into the 110v mains circuit on the boat. The result being 110v 'shorepower'.

Appliances would either be 12v (eg fridge, vhf, gps, stereo etc and therefore no problem as powered by domestic batteries) or UK 240v (eg kettle, fan heater etc) running on mains power. The only exception being the battery charger which would remain 110v. Providing sockets are changed to three pin 240v this would be ok?

Is that correct?

Sorry if I seem a bit thick

 

[rustybarge]

Hi C,

Cheapest idea is to go to a tool hire Co. , they will have step down transformers used on building sites (compulsory for outside use), they convert 240 v down to 110 volts.

You will need 20 amps approximately. For marina 4 pin blue socket.

Everything will run fine at 50cycles except USA Pc's., usa Tv will not like it much.

American electric motors will run fine at uk 50 cycles.

 

[stearman65]

Hi C,

Cheapest idea is to go to a tool hire Co. , they will have step down transformers used on building sites (compulsory for outside use), they convert 240 v down to 110 volts.

You will need 20 amps approximately. For marina 4 pin blue socket.

Everything will run fine at 50cycles except USA Pc's., usa Tv will not like it much.

American electric motors will run fine at uk 50 cycles.

This is rubbish, 50 & 60 cycles equipment is incompatable unles it states it on the power supply unit such as some laptop & camera chargers.
Stearman65.

 

[rustybarge]

Hi steerman,


Ac motors are not frequency sensitive, they will run at anything between 45 - 75 hz ,it makes no difference.

So all USA fridges, microwaves, cookers, air C , will run on 50hz.

But....chip controlled washing machines won't like it.

 

[Mistroma]

This is rubbish, 50 & 60 cycles equipment is incompatable unles it states it on the power supply unit such as some laptop & camera chargers.
Stearman65.

I doubt that there are many laptops around that won't handle 100-240V at 50-60Hz. I remember the issue coming up a very long time ago and the company I worked for had a stated aim of moving to a universal power supply that would work in any market. Much cheaper than building different ones for each area. I know that our major competitor was doing the same thing (no big surpirise). Not certain when it was implemented but am pretty certain it was being worked on more than 10 years ago. So that covers HP & Dell laptops for around 7-8 years. I'd be very surprised if others had not been pushed in the same direction.

I've just remembered that HPs iPAQs also had universal power supplies as did all HP phones. So I'd also be surprised if other manufacturers of small devices didn't do the same thing. HP never went to a completely universal supply as some iPAQ supplies used market specific plugs. I think all the phones had clip on adapters and laptops had swappable plug leads.

However, as you say, it is worth having a look before plugging something in to mains power.

100-240 & 50-60Hz covers the globe pretty well. I remember that Japan was a bit weird in having both 50 & 60Hz at 110V. There was at least one other country with a mix of 110 or 240V at 60Hz so supplies were designed to handle any combination.

 

[William_H]

110 volt equipment on 240v AC

Firstly AC induction motors will not be happy on 50 hertz when they are made for 60 hertz. They go slower and may overheat with insufficient inductance in the motor windings.
So a 110v 60 hertz AC fridge or aircon would be no good on 240 v 50 hertz with a transformer. Likewise electric fans. Anything using heating will be no problem. Except that for hot water heaters electric kettles etc the transformer would have to be so big and expensive that replacing the element, room heater or kettle would be cheaper. So you are most likely left with battery charger as the device which might be worth running on a transformer. You may find a modern charger will run on 110 to 260vAC 50 or 60 hertz. If it has a transformer internally then the 50 hertz in lieu of designed 60 hertz may cause overheat of transformer. But again it may be OK.
Generally replace all equipment that runs on mains power and as said the boat wiring should be fine but cbs fuses etc may be too high rating. Of course replace sockets. good luck olewill

 

[maxi77]

A few years ago I bought a house that had been used by a US company for execs on loan to their UK subsidiary, it had both 240 and 110v wiring run from tool transformers, so it would seem most if not all US domestic kit will run from transformed UK mains.

 

[Norman_E]

Thanks to all so far.

So,

The yellow box I have seen on USA boats has a 240v shorepower lead and plug going in to it on one side and a 110v plug and cable into the 110v mains circuit on the boat. The result being 110v 'shorepower'.

Appliances would either be 12v (eg fridge, vhf, gps, stereo etc and therefore no problem as powered by domestic batteries) or UK 240v (eg kettle, fan heater etc) running on mains power. The only exception being the battery charger which would remain 110v. Providing sockets are changed to three pin 240v this would be ok?

Is that correct?

Sorry if I seem a bit thick

If that is the case and there are no other built in 110 volt appliances then aside from changing the sockets the main item you will need to replace is the battery charger.

 

[William_H]

110v appliances

A few years ago I bought a house that had been used by a US company for execs on loan to their UK subsidiary, it had both 240 and 110v wiring run from tool transformers, so it would seem most if not all US domestic kit will run from transformed UK mains.

This could be very misleading. Appliances run from 2 or 3 watts consumption to 2000watts. I feel sure that there must have been an indication of the limitations of appliances running on 110v through the transformer . ie only for electric razors and small chargers. A transformer to supply 2000w to a space heater or airconditioner or electric kettle would be huge. olewill

 

[oceanpilgrim]

hi
i imported a US yacht 7 years ago,went and bourght a yellow 110 transformer from travis diy,boat has run on it since then no problems so far,i went for the 3.5 kw as i have an emershion heater built in + the air con
dont forget the colors are not the same black and white and green

 

[npf1]

Often wondered about the complications of having a USA spec boat with 110v shorepower system. I have seen them with yellow box transformers in the cockpit but is this a long term solution for a permanent import?

Comments and experience appreciated. What works/does not work? Any regrets?

TIA

My boat has US electrics, lots and lots of it. It's been here in the Uk since 2005 and I've never had any need to want to convert it. The charger I have runs from both and whenever I need 220-240V, I use a small inverter. For the 110V stuff on board, the boat has a large inverter, so I just run that them on batteries, although I did change a few US mains things to 12V, such as the fridge.

Laptops, phone charger etc are no prob as they work on both.

I did have a 5kw soft start step down isolation transformer made by a local specialist (about £350-£400 IIRC), but I've never got around to fitting which sorta shows that the need to be on UK power hasn't arisen. Plus it's heavy lump and I don't fancy installing what must be a 40kg bit of kit that I'd rarely or never use.

As for replacements when stuff dies, I'd rather buy most of it in the USA anyway as it's cheaper. Or buy 110 stuff from here when it comes up as it's dirty cheap. For example, I bought a spare inverter (same 2.5kw make and model as I have fitted) and a few other bits secondhand for £50 from someone who was daft enough to spend £10k+ converting their boat from US to UK electrics to solve a problem that they percieved existed, but in reality didn't.

From a long-term cruising point of view, I would also rather keep it at 110V cos if I ever make it back across the pond, it wil be mightily convenient.

 

[maxi77]

This could be very misleading. Appliances run from 2 or 3 watts consumption to 2000watts. I feel sure that there must have been an indication of the limitations of appliances running on 110v through the transformer . ie only for electric razors and small chargers. A transformer to supply 2000w to a space heater or airconditioner or electric kettle would be huge. olewill

The one I have left is 2.5KW and is just portable though newer ones are lighter. They ran a dishwasher, washer dryer and plenty of other stuff. The transformer I have did the 4 bedrooms with multiple sockets in each room. Fortunately septic plugs and sockets are not the same as ours so the chances of plugging the wrong item into the wrong socket were remote.

 

[Heckler]

This is rubbish, 50 & 60 cycles equipment is incompatable unles it states it on the power supply unit such as some laptop & camera chargers.
Stearman65.

sorry matey, you are wrong, as stated by others on here. Africa, middle 80s, warehouse man ordered Porta Cabins from Houston, american wired with 110v systems including walkin freezers and coolers. THen ordered 50 hz Cat gennies because he thought most of the equipment would come from the UK. I convertd the Cats to 60hz by increasing the speed from 1500 to 1800 rpm. That took care of the kitchen equipment . The rest of the Brit equipment worked fine even tho it was 50 hz. Even the teles and vhs players. As another said, american boats would be wired with thicker wires than european boats, less volts equals more amps. So just change the sockets to UK type, check the charger to see what it needs and check the immersion heater to see what that needs, propably an element change is all. The rest of the stuff will be 12v so not to worry.
Stu