Charging a 12v batt. ?

[MikeP]

I have a12v batt for Genny starting and another one for some small electronic loads. They are both charged by a charger when the genny is running or shore power is connected. They are not charged when cruising unless the genny operating. But I soul like them to be charging when the main engines are running

I'd like some suggestions on the best way to do that,primarily for the electronics batt.

Maybe a small second 12v charger connected only to the electronics batt and connected to inverter power? That way the batt would be charged by the inverter but since the mains are running and charging the 32v system, there would be no drain on them at all. But if I did that I would have to manually turn off the small charger when we anchored so it wouldn't pull any load through the inverter.

Thoughts or comments?

 

[q240z]

Toss an auxiliary one-wire 12v alternator on your favorite main engine and go boating.

 

[yachtsmanbill]

Thanks Q240... but how do you regulate float versus equilize charge? What if it loses water? LOL
Yep, thats just what I am gonna do this winter. I put 2 delcotrons on my Roamer 20 years ago and that removed a myriad of problems associated with the charging system!
Just an FYI... the rebuilt 32 vdc main alts are one wire, self exciting and internal regulators. I still have to remove Dr Frankenheimers regulators' and bubbas wiring job this winter. ws

 

[rsmith]

I have a12v batt for Genny starting and another one for some small electronic loads. They are both charged by a charger when the genny is running or shore power is connected. They are not charged when cruising unless the genny operating. But I soul like them to be charging when the main engines are running

I'd like some suggestions on the best way to do that,primarily for the electronics batt.

Maybe a small second 12v charger connected only to the electronics batt and connected to inverter power? That way the batt would be charged by the inverter but since the mains are running and charging the 32v system, there would be no drain on them at all. But if I did that I would have to manually turn off the small charger when we anchored so it wouldn't pull any load through the inverter.

Thoughts or comments?

We have a Newmar in the plane that drops from 28v Dc to 13.6 and powers a couple of 12v receptacles in the back for pluging in PED's I think the input is 24-48vdc and output is 13.6vdc 30amp. It would keep you from overloading your inverter with a AC charger.

 

[Pascal]

if the genny battery is only used for the genny then you dont' have to worry about it for those short times off shore/genny.

for the electronics, why dont you use a 32 to 12v converter to power them and keep the battery as a back up, using an on/off switch batt switch to switch power source if the converter goes bad.

 

[SeaEric]

Why not add a solar charger? The 52 Hatt CPMY on F dock at Piney has solar panels on top of it's arch. You don't even know they're there. These were intended to keep a charge going if all else failed.

 

[rsmith]

Why not add a solar charger? The 52 Hatt CPMY on F dock at Piney has solar panels on top of it's arch. You don't even know they're there. These were intended to keep a charge going if all else failed.

I got one of those west marine solar panels for my 13 whaler worked great for 3 years but the sun cooked it. It wasnt a cheap one($225) but they wouldnt warant it. How long should these panels last?

 

[Boatsb]

Toss an auxiliary one-wire 12v alternator on your favorite main engine and go boating.

That's just too easy. How complicated can this become? Keep posting please this is interesting.

krush pleas chime in too.


FWIW the alternator on the main with a solenoid that breaks the charging circuit if the genny is running would be the best and easiest solution but why stop there.

If we use a heat concentrator on the mains and take the exhaust water outlets we can create steam and run a turbine to spin an alternator and make the 12V out of wasted heat energy and probably get an article about it in a magazine. 2-300 hours of engineering time plus the building of the components and fine tuning of the system should still be under $100,000.00.

 

[REBrueckner]

MIke,
Sounds like these are the only 12volt batts aboard? then options are enumerated above except for a wind generator(not recommended). Or you could tow a water powered generator (also not recommended).

If you have another 12 volt bank being charged while running, a battery parallel device (combiner) is the way to go.

I like Pascal's suggestion best: "why dont you use a 32 to 12v converter..."

 

[q240z]

If we use a heat concentrator on the mains and take the exhaust water outlets we can create steam and run a turbine to spin an alternator and make the 12V out of wasted heat energy and probably get an article about it in a magazine. 2-300 hours of engineering time plus the building of the components and fine tuning of the system should still be under $100,000.00.

Oh, that's good. I was gonna suggest getting a treadmill for your admiral as an alternative, but your idea's a MUCH easier sell. lol

 

[GJH]

I have a 12 volt generator starter battery that also powers some low draw seldom used items like a couple of tank monitors and the solenoid cut off for the thruster bank (in lieu of a battery switch). A little Pro Mariner charger that operates when the genset or shore power is on works just fine. All other 12 volt stuff on the boat, some electronics, the KVH receiver, etc, run off one of two 32-12 converters.

Now, I would like to know how people have hung additional alternators off their mains, because high on The List is adding a 24 volt alt for my inverter bank, the lack of which I consider to be a flaw in my system, over-working the genset some and the inverter batteries too. I'd probably add a combiner and charge the thruster bank too, which has its own charger similar to the genset set up.

Any pictures or experience with this?

 

[SKYCHENEY]

One more idea:
Hook up the inverter to run everything on the panel. Then you can switch on the 12v charger at any time.

 

[jim rosenthal]

I like the idea of the 32-12v converter, myself.