Electrical System on an Old Boat

[lonesoldier0408]

In battery maintenance, I understand a higher voltage is used to de-sulfate the batteries. Or is it higher Amperage?

[skipmac]

Originally Posted by lonesoldier0408

In battery maintenance, I understand a higher voltage is used to de-sulfate the batteries. Or is it higher Amperage?

I think you are referring to battery equalization which is periodically charging at a higher voltage but only after the batteries are fully charged.

Amperage will depend on the voltage difference between voltage level of the charger and the state of charge of the batteries. If the batteries are discharged (so low voltage) and the charger set to a high voltage then more amps go to the battery, limited by the capacity of the charger. As the batteries are charged up their voltage increases and fewer amps go to the battery if the charger voltage stays the same.

[Cadence]

Originally Posted by skipmac

Have you taken a volt meter and checked the voltage from the batteries or at the electric panel. Can you dram a diagram of how the batteries are wired together? It would help if you could tell if the batteries are wired in series or parallel.

Another idea, there should be a small plate or label on all the electric equipment that will tell what voltage it needs.

99.99% the boat would not be 32 volts. Due to the way batteries work it would almost certainly be some multiple of 12 like 12, 24, 36, 48. I'm not sure if I've heard of a 36 volt system. 12 and 24 are the most common and most likely.

Don't count out a 32 v system. I doubt that is what he has but those bastard systems where used. 4 8V batteries in series. With that and probably a 36V, if in fact that is what he has? Throwing most every piece of electronics over board would be a good starting point. Don't forget the light bulbs.

[skipmac]

Originally Posted by Cadence

Don't count out a 32 v system. I doubt that is what he has but those bastard systems where used. 4 8V batteries in series. With that and probably a 36V, if in fact that is what he has? Throwing most every piece of electronics over board would be a good starting point. Don't forget the light bulbs.

Yes the OP posted a photo of the charger and it is indeed a 32 V system. Definitely a first for me. So yes, the thing to do is update the whole boat to 12V. Even 24V stuff is not so common and can be expensive. But that might entail a complete rewire to handle the higher current to run 12V equipment.

[Stu Jackson]

Originally Posted by skipmac

I think you are referring to battery equalization which is periodically charging at a higher voltage but only after the batteries are fully charged.

Amperage will depend on the voltage difference between voltage level of the charger and the state of charge of the batteries. If the batteries are discharged (so low voltage) and the charger set to a high voltage then more amps go to the battery, limited by the capacity of the charger. As the batteries are charged up their voltage increases and fewer amps go to the battery if the charger voltage stays the same.

That's true for a regular charge. For a proper equalization, the charger should limit the amperage with the higher voltage.

[Cadence]

Originally Posted by skipmac

Yes the OP posted a photo of the charger and it is indeed a 32 V system. Definitely a first for me. So yes, the thing to do is update the whole boat to 12V. Even 24V stuff is not so common and can be expensive. But that might entail a complete rewire to handle the higher current to run 12V equipment.

God bless him. If he has bilge blowers they are going to have to go and who knows what else. The engine starter and probably generator, I doubt it's an alternator, unless only the house batteries are 32V.

My father went through this 50 yrs. ago. He did replace all of the wiring harnesses.

[Scott Berg]

OK; 32 Volt Systems are actually QUITE common on older motor yachts but not on most cruising boats. You will find them on almost all old Hatt's Chris Crafts, etc. It's a common Railroad voltage as well. Most 32v yachts use four 8-19 Batteries in series per bank. And, most use a voltage converter to handle 12v electronics. From where I'm typing this I can see 8 32 Volt boats. If you are considering converting to the more common 24 volt you may be able to keep most of the distribution wiring. A 12v conversion will require removing so me wiring in most cases. Almost all the Hattaras wiring was 10AWG making some log current conversions fairly easy. Oh, and for what it's worth Outback makes a great 32v inverter/charger...

Some gear is indeed still available in 32 but not most modern electronics. That's what the 32 > 12 Newmar converters are for. I work almost full time on and am the captain of several 32 volt Hatt's and Chris's; PM me for specific suggestions...

[Terra Nova]

32-volt systems were common on larger boats built in the '60's. My 1963 48' Grandy Marlineer had such a most excellent system, 2 banks of (4) 8-volt batteries that ran nearly the length of the engine room. On larger boats, wire size becomes a problem, for 12-volt systems, due to the impracticality of up-sizing wire gauge to minimize voltage drop over such long runs. Nowadays 24 volts has become standard on larger boats, as this can easily be created using more readily available 6 or 12 volt batteries. It is then a simple matter to also obtain 12 volts by utilizing only a portion of this 24 volt bank; this is what normally feeds the minor, low power electronics/electrical equipment.

OP--after reading your questions and comments I am convinced that you should get professional help with your system. By all means read Calder and anything else. But don't assume you will then be ready to tackle what appears to be a complete boat re-wiring, yourself.

[skipmac]

Originally Posted by Stu Jackson

That's true for a regular charge. For a proper equalization, the charger should limit the amperage with the higher voltage.

Yes that was my understanding but have seen comments on other threads that chargers that are constant current or current limited are not the norm. Any experience or comments on this? Since I have kept my system very topped off I have not yet played with the equalization setting on my Victron so no idea how it will operate.

[Bonvivant]

Originally Posted by Sailmonkey

32 volts isn't uncommon on older commercial applications. It's done with 8 volt batteries.
But equipment is hard to find and selection is limited.

InterstateBatteries.com

That's quite interesting. I know I should refit, but it would be interesting to see if the autopilot worked when it had 32V going to it. I'd like to keep the boat as original as possible, but I know there are certain things that just can't be kept.

[Cadence]

Originally Posted by skipmac

I think you are referring to battery equalization which is periodically charging at a higher voltage but only after the batteries are fully charged.

Amperage will depend on the voltage difference between voltage level of the charger and the state of charge of the batteries. If the batteries are discharged (so low voltage) and the charger set to a high voltage then more amps go to the battery, limited by the capacity of the charger. As the batteries are charged up their voltage increases and fewer amps go to the battery if the charger voltage stays the same.

About the soundest explanation I've seen. I've seen a bunch of posts trying to make it nuclear physics.

[Cadence]

Originally Posted by Bonvivant

That's quite interesting. I know I should refit, but it would be interesting to see if the autopilot worked when it had 32V going to it. I'd like to keep the boat as original as possible, but I know there are certain things that just can't be kept.

I believe you said it is a 65 Chris Craft? Is my assumption wrong that it is wood? I hope you have had a reputable survey done prior to investing a ton of money. I don't mean sound negative but given your explanation of the wiring, I hope you aren't embarking on a pipe dream.

[skipmac]

Originally Posted by Cadence

I believe you said it is a 65 Chris Craft? Is my assumption wrong that it is wood? I hope you have had a reputable survey done prior to investing a ton of money. I don't mean sound negative but given your explanation of the wiring, I hope you aren't embarking on a pipe dream.

Wood sailboat. For the whole story go here. http://www.cruisersforum.com/forums/...on-100809.html

[hellosailor]

Over a year down the line, and really the big question is whether you have had the boat surveyed yet. A wood boat can go from "needs work" to "impossible to save" in well under a year. And even "needs work" can make your eyes bug out when you see an estimate, because the work is labor intensive and very few yards will even do it, let alone do it properly.

Yes, any carpenter could do it...the problem is to keep the boat from sinking while the carpenter learns about wooden boats and special issues they have.

Given an old foreign built boat, with an oddball electrical system that your father probably modified or converted on an individual basis over the years...I think your best bet is to get a marine electrician down to the boat. Let them examine everything, explain to you what all the pieces are, and make sure to take notes and put durable labels on things. That could easily be $200-250 for two hours plus travel time, but it is worth getting all that information correct and getting it quickly, in case you need to make pumps run or something similarly important that could literally cost you the boat. (And an electrical accident leading to a fire on a wooden boat is also a consideration, you do not want that. You may also want to make sure there are adequate fire extinguishers on board.)

Sounds like a beautiful boat and I hope one worth saving, but whenever someone says "old. wood. boat." those three words at the same time can easily cost five or SIX figures before you turn around. Electrical system? Petty change compared to the larger issues.