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Galvanic Isolator or Isolation Transformer

We're in the process of specifying our boat that will be built next year and I'm wondering which form of galvanic protection I should have? We will be spending many months moored in a marina connected to shore power surrounded by many other boats. I know I need some form of protection and having read about Victron's Isolation Transformer I'm wondering if I need to spend that bit more to have the ultimate protection?

Asked by: Raymond Fowler  | 5.54am, Saturday 5 November

WW says:

Isolation transformers provide the ultimate separate between shoreside power supplies and the boats system. Not only do they separate the earthing bonding system, but they keep the line (live) and neutral apart. This is the usual standard (not even considered the "gold standard", but the norm) for larger vessels, as it gives high levels of protection to the onboard electrical systems, not just from stray earth eddy currents, but surges and overvoltage.
A downside of an isolation transformer is, as it is a transformer, it is not 100% efficient, so there is power loss. However, they are very effective- there is some doubt as to how well some galvanic isolators actually work (and I have seen some poorly installed where there is a break in the earth supply, which is dangerous). Considering the cost in relation to a new boat, I would strongly consider an isolation transformer over a galvanic isolator in a new-build boat.

Mark Langley  | 8.43AM, Saturday 5 November

Readers say:

Thank you, Mark, you confirmed what I was thinking from what I've read on the manufacturers website.

Raymond Fowler  | 6.12PM, Sunday 6 November

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