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Your isolation transformer experience?

Posted: Sun Nov 20, 2016 7:44 pm
by P-Dogg
http://shop.pkys.com/Victron-Energy-Iso ... _2429.html

http://www.defender.com/product.jsp?pat ... &id=614209

Am considering adding isolation transformers to the boat. Does anyone have any experience with either of these two isolators, or a different one? Victron is reported to be quieter, but is it $120 quieter? Anything I need to be on the lookout for when I undertake this project?

Re: Your isolation transformer experience?

Posted: Sun Nov 20, 2016 9:35 pm
by Reel Easy
I may sound like a dummy but what is that and what does it do?

Re: Your isolation transformer experience?

Posted: Sun Nov 20, 2016 9:47 pm
by WayWeGo
If we went to isolation transformers on our boat, I would want to add the ability to boost the output voltage for those times when you are at the end of the run and voltage is below spec. Of course, that usually costs more....

I think you could also save some money by going to the 3.6kVA Charles unit as you probably need two 120V transformers for twin 120V 30A circuits. Or is your boat wired for 240V 50A?

Re: Your isolation transformer experience?

Posted: Mon Nov 21, 2016 6:14 pm
by P-Dogg
Reel Easy wrote:I may sound like a dummy but what is that and what does it do?
Description in defender link. They electrically isolate your boat from shore power, making galvanic corrosion and electrocution all but impossible. See also http://www.boatus.com/seaworthy/magazin ... ormers.asp

Re: Your isolation transformer experience?

Posted: Mon Nov 21, 2016 7:32 pm
by P-Dogg
WayWeGo wrote:
I think you could also save some money by going to the 3.6kVA Charles unit as you probably need two 120V transformers for twin 120V 30A circuits. Or is your boat wired for 240V 50A?
Twin 30A. I'd pay more for quiet, but of course no one has simultaneous experience with more than one brand, so everything is pretty subjective. In the scheme of things, 2.5 boat dollars is nothing.

Re: Your isolation transformer experience?

Posted: Tue Nov 22, 2016 7:04 am
by prowlersfish
We were talking about this the other day on the dock . The issue of noise never came up ( no idea of the brand ) . I do know galvanic corrosion is not eliminated 100% as the zincs are still doing their thing ( most likely from outside sources ). On the Shock factor , the risk to swimmers is much greater in fresh water then salt . Not sure about electrocution being 100% eliminated . Their have been electrocution of swimmers From gen sets when on the hook .( All cases I have heard of were in fresh water ) So the boat wiring must be 100% right , regardless . Just my thoughts

Re: Your isolation transformer experience?

Posted: Tue Nov 22, 2016 7:00 pm
by P-Dogg
I count on your thoughts Paul! Pardon me for posting in a hurry before...

Galvanic corrosion is not what is eliminated -- isolation transformers protect against stray current corrosion, the kind that dissolves your underwater metals and is driven by shore power leakage (not necessarily from your boat). See:
http://www.boatus.com/Assets/www.boatus ... rosion.jpg


As for electrocution, I was considering the case of being at the marina, in brackish water, where I dock. Of course I could be electrocuted by other peoples' boats, but my sense of personal responsibility causes me to do what I can to reduce risk. And for the record, because my boat spends most of its time in brackish or fresher water, I don't use zinc anodes, I uses aluminum.

Here is an article that discusses the merits of isolation transformers:
http://www.boatus.com/seaworthy/magazin ... ormers.asp

And here is the best discussion that I have found regarding the merits of various types of isolation transformers:
http://www.cruisersforum.com/forums/f14 ... 57167.html

Re: Your isolation transformer experience?

Posted: Wed Nov 23, 2016 10:42 am
by WayWeGo

Re: Your isolation transformer experience?

Posted: Wed Nov 23, 2016 1:21 pm
by mikeandanne
Lots of great info here guys, very relevant to this problem of dangerous stray currents and corrosion....good stuff, great read...Mike

Re: Your isolation transformer experience?

Posted: Fri Dec 23, 2016 1:39 pm
by Misty
Yeah in fresh water I would say you are adding for safety rather than conserving UW metals. So in that vein it will only be as good as the rest of your system AND ANY MARINA YOU PLUG INTO. If we get into a paranoid discussion here I find about 1/3 marinas in the northwest were wired by someones drunk cousin etc... and exhibit problems at the pedestal. Not to mention neighbors. For that reason I wouldn't swim at a marina but divers and people who fall in well... It only takes a very small current to mess up a heart beat. Could it kill someone? Who knows.