Galvonic Isolator- Where and how is it connected?

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Red5
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Galvonic Isolator- Where and how is it connected?

Post by Red5 »

My meter went south a few years ago. The other day I pulled it and found that only the + was connected. Is this correct? It has a place for the negative but it looks as if it has never been connected.

Do I need to find a loose wire somewhere?
37 Sedan Twin CAT 3208's "Under Way is the Only Way".
bpboater
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Re: Galvonic Isolator- Where and how is it connected?

Post by bpboater »

I think you are talking about the capac galvanic corrosion meter - correct? There is a galvanic current isolator used in the incoming 120 vac power line to prevent current leakage on the green ground wire of the shore power cable. On the galvanic isolator device, only the green ground wire goes in and out the isolator. I am unsure which capac meter you have.
1988 41 Marinette
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jralbert
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Re: Galvonic Isolator- Where and how is it connected?

Post by jralbert »

I was thinking the same thing as bpboater. The galvanic isolator and the capac meter are different and unrelated devices. The Capac meter usually was installed below/under the helm and is, well, it's a meter with a dial. It does have two connections. That's what you appear to be referencing in your first words (meter).
The other thing, mounted in our 1988 FBS in the storage area under the interior stairs, keeps you from getting electrocuted and has, as bpboater notes, one green wire.
-joel-
former owner 1988 '32 FB Sedan
Chesapeake Bay
twin 318 / 240 hp
Potomac MD
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Busia
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Re: Galvonic Isolator- Where and how is it connected?

Post by Busia »

Your Capac unit is just a "battery" and you measure the voltage with the meter. It is really a cell, multiple cells would be a battery. You can see what happens when you have dissimilar metals and an electrolyte. Here you do it on purpose with the silver/ silver chloride sensor and your hull. You want from.9 to 1.05 millivolts to be produced. More or less means you have too little or too much anode protection. You can just put a digital voltmeter from the sensor to the hull to get the reading. That is all the meter at the helm does. A digital meter will be more accurate too.
If you go to Boatzincs.com you will find more info, and the best prices on anodes. They are so good that you can just call them up and tell them what boat you have and they will know just what you need. Highly recommended.
Last edited by Busia on Fri Mar 22, 2019 2:40 pm, edited 1 time in total.
BUSIA
located in Ketchikan, Alaska. Gods country
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Red5
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Location: Louisville, KY

Re: Galvonic Isolator- Where and how is it connected?

Post by Red5 »

Capac meter is correct. Sorry, was having a brain fart.

Does the meter need to have both a + and - hooked up? Mine did not and I think this is why it isn't working. But I didn't see another wire having around. Thought I would ask before I went looking.
37 Sedan Twin CAT 3208's "Under Way is the Only Way".
jralbert
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Re: Galvonic Isolator- Where and how is it connected?

Post by jralbert »

We're in luck on your behalf. This forum featured a Capac discussion a couple of years ago (which is why doing a search here can save you time. In this case, Ii used Google to search). Voila - scroll down to see the Capac manual I posted. It's not the clearest illustration, I admit, but it's right from the mfr and will be helpful. It does answer the question of one or two wires (two).

http://www.marinetteboat.com/forum/view ... f=26&t=999
-joel-
former owner 1988 '32 FB Sedan
Chesapeake Bay
twin 318 / 240 hp
Potomac MD
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