Understanding the CAPAC

jralbert
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Re: Understanding the CAPAC

Post by jralbert »

I believe Jeff may have made one of these and posted. It was, as I recall, a very simple setup that you dropped overboard and got a quick reading on a voltmeter. It is not good, however, to use as troll bait for rockfish.
-joel-
former owner 1988 '32 FB Sedan
Chesapeake Bay
twin 318 / 240 hp
Potomac MD
barefoot99
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Re: Understanding the CAPAC

Post by barefoot99 »

jralbert wrote:I believe Jeff may have made one of these and posted. It was, as I recall, a very simple setup that you dropped overboard and got a quick reading on a voltmeter. It is not good, however, to use as troll bait for rockfish.

Busia, explains it again. An electric meter set on millivolts , positive lead to your grounding bar in the boat ,negative lead in the water with the reference electrode.( Extra cost ,nice to have in the toolbox) This will give you an accurate reading. It is what a CAPAC meter does as a unit, this is also how you calibrate the CAPAC meter in your boat.
SUP !
1982 32 Sedan FB
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Fastjeff
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Re: Understanding the CAPAC

Post by Fastjeff »

The probe I bought was not THAT expensive, as I recall. It can work with an ordinary volt meter.

Jeff
"We live at the bottom of an ocean of air, not at the top." General Marvage Slatington
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Busia
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Re: Understanding the CAPAC

Post by Busia »

BoatZincs.com has them. look under tools. This and a little digital VOM meter, which you should have for other tests, and you can test more accurately and cheaper than trying to fix the CAPAC system in the boat.


Corrosion Reference Electrode and User's Guide by ABYC-Certified Corrosion Experts
List Price: $199.99
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A portable silver/silver-chloride electrode
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surveys on yachts and boats.
Good site to go to. Read, and learn all the facts, and order more anodes.
(thanks for the eraser, we don't need spam)--Ed
BUSIA
located in Ketchikan, Alaska. Gods country
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Fastjeff
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Re: Understanding the CAPAC

Post by Fastjeff »

Wow! Those have really gotten expensive.

Jeff
"We live at the bottom of an ocean of air, not at the top." General Marvage Slatington
barkleydave
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Re: Understanding the CAPAC

Post by barkleydave »

Yes glad I bought mine 20 years ago... LOL
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wschneid
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Re: Understanding the CAPAC

Post by wschneid »

I have a Marinette 32 Fly Bridge Sedan 1986. The previous owner showed me the galvanic reading of about .9 in salt water. I now have the boat in fresh water and when not connected to shore power I still show .9, but when I connect to shore power it drops to .7. This is second marina I ave been in on this river and I get the same results. Could I have some grounding problem? Any ideas?

Bill Schneider
JohnO
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Re: Understanding the CAPAC

Post by JohnO »

Having a bit of trouble understanding this post. Is low bad or is high bad or both? I have a 28 sedan and the meter shows it should be around .9 I am reading 1.2. The water on Lake Michigan is pretty cold right now and there is a lot of water current going on now in the harbor so the water isn't as clean as it was about a month ago.
John

1984 28' Sedan Flybridge
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jralbert
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Re: Understanding the CAPAC

Post by jralbert »

I think you're ok
-joel-
former owner 1988 '32 FB Sedan
Chesapeake Bay
twin 318 / 240 hp
Potomac MD
Fastjeff
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Re: Understanding the CAPAC

Post by Fastjeff »

..."Is low bad or is high bad or both?"

Yes! You need to be in the range of around ,7 to 1.2 volts (times ten on the CAPAC meter scale).

Jeff
"We live at the bottom of an ocean of air, not at the top." General Marvage Slatington
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