Isolation Transformer for Europe

[ShipShape]

Hi Charlie and Leee - last year I did exactly what you are talking about. The stray current where I was living at the time was Phenomenal, and my research led me to the Charles Iso-G2. It comes with diagrams of different ways to wire it depending on your needs, and I had some questions, which resulted in a phone call to Larry Budd. Apparently there are several ways to wire that transformer beyond the instructions that come in the box, and one of them is to step down European 240V to 120V. Larry e-mailed me diagrams for how to do that - it is simple.

Where your shore power comes in the boat you send it to a three-position, four-pole switch, Blue Sea part #6337. It is a break-before-make switch for switching between shore and gen power, but you just wire it the same way for leaving to two circuit breakers.

So one way, say the "shore" you send it to a 30-amp circuit breaker, and the "gen" setting you send it to a 16-amp CB (hard to find BTW). Then the wires from the two CBs go to the transformer and Larry's diagram shows how to go from there.

As Leee pointed out, the 50 vs 60 Hz IS an issue, however for things without moving parts like lights and heating elements it shouldn't matter.

You still need an adapter for your shore power plug, I haven't looked for one yet.

[Charlie]

Shipshape:

Thanks I had a quick read and that makes sense to me. I like the idea of a switch w/o any electronics involved. I'll study up on it when I have a little more time.

[ShipShape]

A clarification for the use of the Blue Sea rotary switch for those who don't do a lot of wiring: When you read about the switch it talks about two inputs - shore and gen power, and one output - your AC panel. For the step-down application being discussed here, there is one input: shore power, and two outputs: one to the 30 amp circuit breaker and one to the 16 amp CB. A switch doesn't know if power is coming or going, it just opens or closes a circuit - you can wire it for any application you desire. Here, the output from the switch goes to the isolation transformer, and the input to your AC panel comes from the isolation transformer.

Also, you wouldn't need this switch to step down American 240V to 120V, those are both 30 amps and that can be done with the Charles Iso G-2 (and other step-down transformers) alone. American 240V is the combination of two 120V hots, and European 240 is one hot 240V.

And even though I found the wiring of this isolation transformer to be easy and I encourage people to do their own wiring, if anyone has ever told you that you are not a logical person please don't do it yourself. Like they say, you can kill yourself twice as fast with 240 volts as 120 volts.

[GordMay]

Originally Posted by ShipShape

A clarification for the use of the Blue Sea rotary switch ...

And NEVER switch any rotary switch under load!

[MarkJ]

Originally Posted by Charlie

I am looking at purchasing an Isolation Transformer (IT) for my upcoming trip to Europe. .

I was kinda looking into this a few years ago. I found there is quiet a lot of Americans wanting the same and - low and behold- theres quite a market for them in the Azores!

Seems the entrepreneurs have worked out thats where people will buy them and theres enough being brought in to keep the cost low.

But this was a few years ago (I think 3) so you might want to check up on it now. I remember it was very difficult to find the right stuff in the USA because they think the world only runs on 110


Mark
PS I don't need any of that stuff now because I have solar panels. Hit a marina and its No Sir for the shore power

[Charlie]

Originally Posted by GordMay

And NEVER switch any rotary switch under load!

I understand that you are not supposed to turn a rotary switch when it is hooked up to a 12v system when the alternator is charging because this will cause problems with the alternator. I have never heard not to do it for an AC system. Can you explain why. I remember things better when I know the reason.

[Ultimarv]

Update on our Isolation Transformer challenges for connecting:
- US: 120v/240v 3-pole/4-wire 50-ampere/60Hz for use while in Europe.

Background
Victrons Isolation Transformers has a useful "feature" in that they increase output voltage by 10%. Useful in lower voltage situations.

We installed a Victron 7000w Isolation Transformer that feeds this increased voltage to an installed Victron Autotransformer 32 that steps down power to 2-legs of 120v using a common neutral generated by the Autotransformer.

Outside of the UK, or in lower voltage situations, this is fine. In the UK, where voltage is 240v and sometimes found at 250v, our power protection circuit (part of our orignal US gear) does not let shore power through to the ATS since it is measuring across legs 1&2 and coming up with 250+ volts.

Solution
Marine Energy Shop (www.marine-energyshop.nl) is building us essentially another stepdown transformer that will sit in between the Victron Isolation Transformer and the Victron Autotransformer. In UK voltage situations where incoming shore is 240 or more, it will stepdown the 10% increased voltage back to 240v. In lower voltage situations, mostly outside the UK, a switch will just pass the voltage straight through to utilize the increase provided by the Victron Isolation Transformer.

Summary
I am not sure many will come in contact with this challenge, but I post it just in case you find yourself encountering it. The solution means more gear, more install and more weight, but also more heat, more air con and more comfort in a 50-amp environment.

Our savior during this period has been the Mastervolt 100-amp 3-stage battery charger that accepts shorepower from 95v-260v, along with a 4000w inverter. Of course this meant less heat, less air con and less comfort.

[jason902]

Just a random thought, what about switching around your isolator transformer such that what is nominally the output side, is hooked to shore power and the nominal input side is hooked to your boat's a/c system?

This should lower your voltage by the same 10% it is raising it now, taking you from 240vac to 216vac.

Jason