Types of Galvanic Isolator

[bignick]

One of my jobs to do this winter is to fit a Galvanic Isolator.
Looking online and on eBay there is a massive variation in price. Is it just down to quality, or do more expensive ones offer something other than better components and manufacturing? is there any benefit in going for a Victron or Sterling, or should I just save the money and fit a generic one and spend the difference on better connectors and shorepower leads etc.?? Is there a sweet spot in price Vs performance?
many thanks,
Nick

 

[Poey50]

As no-one has replied I'll have a go at this having researched it myself a couple of seasons ago. The more expensive ones are failsafe - made particularly for the US market to meet the ABYC standard. In this case, failsafe means that the earth connection from boat to shore remains intact retaining protection against electrocution. Less expensive ones presumably fail open (although they don't advertise this fact for obvious reasons) which could leave you with no protective earth connection; a problem which may lay undiscovered. Parts of the US are prone to lighting strikes which for boats in a marina may, with a single strike, wipe out multiple GIs.

If they are failsafe manufacturers will proudly proclaim that fact. If they don't mention it - they aren't. Of course, if they do fail safe, and you don't notice it, there is then no protection to your anodes being eaten by other boats in a marina which was the point of fitting one in the first place.

In the end I installed a Safeshore Marine 70 amp version with remote monitoring. It isn't however failsafe but I try to remember to test it annually. I think there would be one or two other clues if the boat had a lightning strike as we are on a mooring rather than in a marina.

As said in another current thread, there is no point in fitting a GI unless there is a path to earth from your A/C. Many older boats don't have this pathway. I suspect there are many boat with GIs installed that do absolutely nothing. Again, don't expect a seller to mention this!

 

[Nauti Fox]

I "fitted" One of these
Galvanic Isolator - 500 Amp Surge - Plug In Simple Installation - Suitable for ALL Hull Types and Materials - Suitable for ALL Water types - Designed and Made in the U.K. : Amazon.co.uk: Sports & Outdoors

They also do this one.

Galvanic Isolator Marine Status Alert - 500 Amp Surge - Plug In Installs in Seconds - Protects against Galvanic Currents AND Earth Leakage - UK Designed & Built : Amazon.co.uk: Sports & Outdoors

 

[bignick]

many thanks Poey50, I’ve Learned something new. I knew there were monitored and non-monitored, but didn’t know about fail-safe versions. I’ll look into it further.
thanks also NautiFox - I’ll take a look at those.

 

[VicS]

many thanks Poey50, I’ve Learned something new. I knew there were monitored and non-monitored, but didn’t know about fail-safe versions. I’ll look into it further.
thanks also NautiFox - I’ll take a look at those.

You might find this website useful to explore Galvanic Isolators for Boats
It explains why you might need a GI, how to chose one and how to install and test one.
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