Help required in sourcing a step up transformer in the USA

Oscarpop

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We head towards the USA from Antigua next month and have a 220v boat and inverter/charger.


We need to get a 110v to 220v step up transformer, the weatherproof type that you use for tools. Ive attached an image below.. However we can't find anyone in the USA that can supply one.

Does anyone know a mail order company in the USA that has these? I can get one anywhere in the UK, ( they weigh 20kg), but can't seem to find anything over the pond.


Many thanks.P081OZA.jpg
 

TQA

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Heckler

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We head towards the USA from Antigua next month and have a 220v boat and inverter/charger.


We need to get a 110v to 220v step up transformer, the weatherproof type that you use for tools. Ive attached an image below.. However we can't find anyone in the USA that can supply one.

Does anyone know a mail order company in the USA that has these? I can get one anywhere in the UK, ( they weigh 20kg), but can't seem to find anything over the pond.


Many thanks.View attachment 61471
Dont forget, a simple lo tech wire wound one works both ways. I was in florida a few years ago, before auto adjust chargers were the norm, I needed a 240v source so bought an american travel 110v adapter kit which had a transformer to plug into our systems over here to give 110v. I frigged it so that the 110v mains went in and got 240 out to drive the 240v camera charger. Its a bit down and dirty but it works!
Stu
 

jdc

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Although you quite understandably want to do it properly, it's maybe worth noting practice in other 110V countries like Brazil and Suriname.

They run 3-phase mains just as in the UK, but it's 127V (they call it 110V and use US plugs and equipment) per phase. Hence between phases it's sqrt(3) x 127 = 220V. So every marina pontoon has '220V' supplied. It's symetrical about earth so the 'Reverse Polarity' neon is always lit on our panel, and in fact 'live' - earth - 'neutral' is 127 - 0 - 127 but it gives 220V between live and neutral.

Works without any issues with my 220V kit (battery charger, vacuum cleaner, toaster, power tools etc).
 
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Oscarpop

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Many thanks. It is really to plug the boat into shore power, so I we really need a weatherproof one.
The budget marine one is almost $1000, while the tool transformers are $100.

Also we really do not have the space to mount it within the boat, so it needs to sit outside on the dock.

Any further suggestions greatly appreciated.
 

john_morris_uk

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Although you quite understandaby want to do it properly, it's maybe worth noting practice in other 110V countries like Brazil and Suriname.

They run 3-phase mains just as in the UK, but it's 127V (they call it 110V and use US plugs and equipment) per phase. Hence between phases it's sqrt(3) x 127 = 220V. So every marina pontoon has '220V' supplied. It's symetrical about earth so the 'Reverse Polarity' neon is always lit on our panel, and in fact 'live' - earth - 'neutral' is 127 - 0 - 127 but it gives 220V between live and neutral.

Works without any issues with my 220V kit (battery charger, vacuum cleaner, toaster, power tools etc).

Exactly what I've done several times. A careful prod with the multimeter quickly reveals which terminals have 220 between them and everything 230 on board worked perfectly.
 

TQA

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Be aware that US boatyards and marinas may refuse to allow you to connect to their 110v supply if they feel it does not meet some US standard and have a suitable plaque on the side giving approval details.

They refused to allow my transformer set up which had seen me through several Caribbean boatyards and marinas. I suppose the choc block connectors and inverted bucket as waterproofing was a bit Heath Robinson.
 

john_morris_uk

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Be aware that US boatyards and marinas may refuse to allow you to connect to their 110v supply if they feel it does not meet some US standard and have a suitable plaque on the side giving approval details.

They refused to allow my transformer set up which had seen me through several Caribbean boatyards and marinas. I suppose the choc block connectors and inverted bucket as waterproofing was a bit Heath Robinson.

Have a nice smart plug and a smart lead into the boat and hide the Heath Robinson bits out of sight?
 

Chalker

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In US marinas you can usually get what are known as 30A and 50A supplies. A 30A socket will need a transformer. A50A socket has two 110v supplies of opposite phases and a centre ground, giving 110-0-110 or centre tapped 220v.

Connect a UK neutral to one of the 110 connections, UK live to the other and ground to ground. My boat electrics have a two pole RCCB and two pole 16A circuit breakers so I remain fully fused and protected.
This is a very commonly used solution and no transformer is needed. Domestically cookers (ranges) in US kitchens use this system.

You still have the problem that US power is 60Hz and some European equipment will not work. For us the main battery charger, microwave, laptop supply, drill charger and all tablet and phone chargers all worked. The breadmaker and tabletop washing machine did not.

50A supplies cost more than 30A supplies at marinas. If you do not have aircon try to negociate a lower price, US marinas normally have a fixed price per day and 50A supplies are normally used for boats with heavy duty aircon loads.
 
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