I assume this is the galvanic isolator. It's on our 1979 cat 30. Wiring is horrendous on our boat. Something to address one day. Slowly whittling away at things.
Galvanic Isolator
- Thread starter dnimigon
- Start date
Appears to be as I googled it and it looks similar. I avoid having one by not hooking to shore power.
Our 78' was a similar mess when we started. We did not have wire nuts even but did have long bolts used as bus bars. Lovely.
Our 78' was a similar mess when we started. We did not have wire nuts even but did have long bolts used as bus bars. Lovely.
Looks like my battery isolation device. allows the alternator to charge house and start batteries but does not allow the start battery to power the house circuit. It looks like vary large cables that would be DC rated for quite a few amps not AC safety grounds. Also the color of cable would not lead me to believe that they are grounding wires which are universally green.
What do the cables connect to? my guess is one side goes to the house and the other to the start + terminal. The center terminal seems to be unused and would connect to the alternator + output.
They are simple diodes so it is pretty easy to test. If it is a battery isolator the center is connected to each side terminal with a high amp diode. both diodes conduct current away from the center terminal and to the side terminals. If it is a galvonic isolator the two terminals are connected by diodes that allow current to flow in both directions (with a 2ish volt voltage drop accross the terminals of course to provide the "isolation" for galvonic currents in the safety ground circuit).
Good luck and welcome to the club of boat owners with just plain messy wiring.
What do the cables connect to? my guess is one side goes to the house and the other to the start + terminal. The center terminal seems to be unused and would connect to the alternator + output.
They are simple diodes so it is pretty easy to test. If it is a battery isolator the center is connected to each side terminal with a high amp diode. both diodes conduct current away from the center terminal and to the side terminals. If it is a galvonic isolator the two terminals are connected by diodes that allow current to flow in both directions (with a 2ish volt voltage drop accross the terminals of course to provide the "isolation" for galvonic currents in the safety ground circuit).
Good luck and welcome to the club of boat owners with just plain messy wiring.
Bill's right, that's what it is. Diodes drop voltage, so while they separate your banks, they suck for charging properly, literally by sucking voltage. When we got our boat in 1998 it was the first thing I ripped out. It is 1960 "technology" so you should do some research on combiners, echo chargers and ACRs (VSRs).
Like this:
What are ACRs, Combiners & Echo Chargers? (by Maine Sail)
http://forums.catalina.sailboatowners.com/showthread.php?p=742417
see reply #2
Like this:
What are ACRs, Combiners & Echo Chargers? (by Maine Sail)
http://forums.catalina.sailboatowners.com/showthread.php?p=742417
see reply #2
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That is a good start, but you can get a Stray DC current on the AC green wire, from a neighbor's boat connection to AC with out an isolator.
All boats need a galvanic isolator or fix the source of the AC ground power up.
Jim...
What a mess!... my 79 had a mess of wires like that. When I was done I had filled a paper sack from the market with tightly wound automotive and house wire that the previous owners had installed over the years. Included regular old 115 AC outlets from home depot. They still had the price stickers on them. As a note...it was a charter boat ..goes to show you the lengths those outfits will go to when in the 'save a buck' mode., It has taken me several years but I finally think I have eliminated all of the bogus wire, including the mass of 12 volt DC ground wires that were all attached to one poor bolt on the engine starter. It wouldn't be an exaggeration to say there were a dozen wires attached to the one bolt. What is shocking to me is that the gentleman I bought it from claimed to teach "marine electrical" at a local community college with a good reputation. Oh well! Good luck with your project. Don't get discouraged and keep track of what you are doing and check back here and post pictures.
Yes I've been hauling out all kids of wiring too. House wiring also. I think I've taking out about 5 grocery bags so far. The previous owner over time. It is a 79 had equip added, outdated then added more here and there. So I find a loose end, trace it back to nowhere. So get rid of it. Kimelmore. I'm eventually going to be cleaning the whole mess up and probably be getting a new panel as the old one has issues with rust, bad breakers falling apart. I've been looking at some of the Bluesea stuff but the whole thing seems overwhelming. I'm 'm capable of doing it all but there are so many choices. What all did you do in your panel area.
I have kept my stock panels and switches but replaced every wire in the boat. I did replace the one switch that the lightning strike smoked.
Love the retro feel and don't mind the glass fuses.
Love the retro feel and don't mind the glass fuses.