Question on Installing 240vac Outlets

[mikerayburn]

An ELECTRICAL question

I’m thinking of installing a few 240v outlets, with a separate shore power connection, for use in Europe and Asia. This would be a typical 3 wire system, not like the 240v US 4 wire systems.
I can’t see why I need to be concerned with reverse polarity or galvanic isolator as it would not be grounded to anything on the boat. A separate connection would be run thru a 2000W step up/down transformer or a separate circuit provided for the transformer which I think will provide the isolation. Am I missing something here?

The system would be: shore power to main breaker, feeding 3 or 4 breakers, one that would feed the step down transformer, the others feeding 240v lighting or appliances only.

Comments appreciated.

Mike

[Mr B]

where are you for a start,

USA has 110 Volts,

Australia has 240 Volts, 3 wire, Standard,

[GordMay]

See ISO 13297 - Small craft Electrical systems - Alternating Current
➥ http://earlhill.de/files/ISO_13297_S...tallations.pdf

[mikerayburn]

let me restate the problem.
An ELECTRICAL question
I have a fully ISO compliant 120v system with 2000w inverter. All standards are written assuming a 120v or 240v systems. I understand the possibility of stay current making its way thru the grounding system and engine thus setting a ground with the water. This would create two grounds (boat, shore power) with a difference of potential between them.
I’m thinking of installing a few 240v outlets, with a separate shore power connection, for use in Europe and Asia. This would be a typical 3 wire system, not like the 240v US 4 wire systems.
However, I can’t see why I need to be concerned with reverse polarity or galvanic isolator as it would not be grounded to anything on the boat. A separate connection would be run thru a 2000W step up/down transformer or a separate circuit provided for the transformer which I think will provide the isolation. Am I missing something here?
The system would be: shore power to main breaker, feeding 3 or 4 breakers, one that would feed the step down transformer that feeds the 120v system. The others feeding 240v lighting or appliances only.
The question is how could this create a hazard? From what i can see the standard don’t recognize the limited use of two voltages but look at each as it was the only one, thus requiring reverse polarity or galvanic isolator on both. A belt and braces approach.
I’m beginning to think it might be cheaper to get rid of the 120 tools and appliances and change the connection to the inverter and buy a new element for the water heater and just go to a 240v system.
Comments appreciated.
Mike