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Old 29-05-2019, 16:59   #1
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Which Galvanic Isolator?

I need to install a Galvanic Isolator but Googling hasn't yielded much in terms of reviews & recommendations.

I don't understand the difference between a 30amp and a 60 amp (nor the very small price difference between them).

Boat runs on 50 amp shore power. Installing a GI appears simple...

Could anyone recommend an appropriate Brand/Model?


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Old 29-05-2019, 18:19   #2
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Which Galvanic Isolator?

I think as long as you stay with an established name brand, you canít go wrong.
As a swag most any mid priced one Defender sells is most likely good.
Very simple thing actually and if like mine itís mounted where it will normally never be seen.
Itís my understanding that if you have a 30 amp Boat, a 30 amp isolator is sized for you, I donít think it would be bad to fit a bigger one, but why?

Not saying buy from Defender, just that they seem to do their homework and seem to sell good products.
Mine happens to be a Promariner, which means nothing of course.

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Old 29-05-2019, 21:03   #3
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Re: Which Galvanic Isolator?

if the boat has a 50a shore plug then you'd need a 50 or 60a isolator.

you want a fail safe one. this one would be fine

60 A ProSafe Isolatr FAIL SAFE | ProMariner
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Old 29-05-2019, 21:37   #4
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Re: Which Galvanic Isolator?

A galvanic isolator blocks DC electricity from entering the boat, thus preventing setting up a galvanic cell (or stray currents) that might cause loss of underwater metals. Galvanic isolators are part of the ABYC recommendations, and are very desirable - as far as they go. A better approach would be to install an isolation transformer, which not only blocks DC currents but also isolates the AC system and thus avoids some safety issues. Isolation transformers can also have extra taps for stepping up/down the voltage; mine can take either 110V or 230V input and output either one as well. This is very convenient for American boats visiting 230V countries. Another feature is to provide an optional boost to the voltage on some units. If you are in a poorly-wired marina (not uncommon) and are only getting 100V at the dock a boost might bring the voltage back up to 110V for operation on the boat. All this costs money of course - an extra $1k or so more than an isolator for a basic 50a transformer and up from there.

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Old 30-05-2019, 03:58   #5
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Re: Which Galvanic Isolator?

Galvanic isolators are covered by ABYC Standard A-28 GALVANIC ISOLATORS - Current Version: 2014
2008 Version ➥

Pro Mariner ProSafe FS (Fail Safe) Galvanic Isolators
ProSafe FS Series | ProMariner

Newmar Galvanic Isolator #GL-50

Yandina Galvanic Isolator #GI-50N

DEI Marine Fail Safe Plus 50/60 Amp Galvanic Isolator #DEI-GI-50/60A-FSP
Gord May
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galvanic isolator

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