Tripple Batteries

[Hardcorr]

I've done a search and am unable to find any info on setting up a triple battery set up.
I'm setting up a 24V winch and am thinking that I can run two batteries that are devoted to the winch and connect them up to give me 24V. I am also wishing to run a third battery that will be devoted to standard vehicle power.
I was going to just extend the dual battery set up that I already have and add a third battery with a solenoid set up the same as the duals.

Is this way OK to do, or is there a better way to do it?

Cheers
Corry

[drivesafe]

Hi Hardcorr, you COULD do it that way but a much simpler and much better way would be to leave the 12v system alone and install a separate 24v alternator to charge the 24v battery bank.

This would also have the advantage of giving you much more power when winching

[Hardcorr]

Yeah, I'd love to do that, the only hassle I got is fitting another alternator in there. With all the oil coolers and the V8, there isn't that much room left.
At this stage I'm wondering how I'm going to fit the third battery in.

Thanx for the reply,

Corry

[ausoops]

I've done a search and am unable to find any info on setting up a triple battery set up.
I'm setting up a 24V winch and am thinking that I can run two batteries that are devoted to the winch and connect them up to give me 24V. I am also wishing to run a third battery that will be devoted to standard vehicle power.
I was going to just extend the dual battery set up that I already have and add a third battery with a solenoid set up the same as the duals.

Is this way OK to do, or is there a better way to do it?

Cheers
Corry

to charge a 24v bank you need to have a 24v supply, you cant hook them up in series (24v) and then charge separatley in parallel (12v). you would create a dead short accross the 12-24 battery and have a nice fire on your hands. you need to have a 24v alternator installed to keep them charged.

[drivesafe]

Hi Hardcorr and ausoops, it can be done but the problem is the currents that have to be handled.

Standard solenoids would not take the sort of current that a winch needs, for very long.

There are heavy duty changeover solenoids available, the are used in things like those huge dump trucks used by the coal industry.

Kamatzo dump trucks actually revers the battery polarity in an emergency to convert the electric wheel motors into generators, they then act like massive great brakes, so large change over solenoids are available.

The solenoids you need though, will have to be 12v high current changeover solenoids that have isolated contacts that are rated for at least 24v.

Cheers and good luck.

[me3@neuralfibre.com]

To solve the space problem I run a PC920 Odyssey. Starts the 1HZ easy, and is 1/3 the size, mounts anywhere, anyhow. Discharge resistant, super fast charge etc etc. BUT, not huge capacity, it's for starting only.

Paul

[ausoops]

Hi Hardcorr and ausoops, it can be done but the problem is the currents that have to be handled.

Standard solenoids would not take the sort of current that a winch needs, for very long.

There are heavy duty changeover solenoids available, the are used in things like those huge dump trucks used by the coal industry.

Kamatzo dump trucks actually revers the battery polarity in an emergency to convert the electric wheel motors into generators, they then act like massive great brakes, so large change over solenoids are available.

The solenoids you need though, will have to be 12v high current changeover solenoids that have isolated contacts that are rated for at least 24v.

Cheers and good luck.

it is possible, but as you say you would need a very large auto change over system in order to separate the 24v bank and convert it back into 12 parallel for charging. the contacts in a dump truck would probably be the size of his whole engine bay.

[INDYGQ]

Hi Hardcorr and ausoops, it can be done but the problem is the currents that have to be handled.

Standard solenoids would not take the sort of current that a winch needs, for very long.

There are heavy duty changeover solenoids available, the are used in things like those huge dump trucks used by the coal industry.

Kamatzo dump trucks actually revers the battery polarity in an emergency to convert the electric wheel motors into generators, they then act like massive great brakes, so large change over solenoids are available.

The solenoids you need though, will have to be 12v high current changeover solenoids that have isolated contacts that are rated for at least 24v.

Cheers and good luck.

it is possible, but as you say you would need a very large auto change over system in order to separate the 24v bank and convert it back into 12 parallel for charging. the contacts in a dump truck would probably be the size of his whole engine bay.

These dump trucks you are speaking of actully have a 66l quad turbo v16 diesel just to run the altanator to supply the electrcity to the wheel motors.
A lot more involved then a change over relay.

[rockcrawler31]

Is it not possible to have two batteries operating in series for the winch but have a 12v alternator connected up to ONE of them to provide charge at 12v that is then spread over two batteries being in series?

Not sure if i'm describing it right.

two batteries in series for 24v

pos and neg from 12 volt alternator goes to pos and neg on ONE of those batteries providing charge. As battery charges it evens out its charge with the other battery by means of it being hooked together?

The reason i am asking this is because i am wondering if it will work the other way. I am building a hot rod truck that will most likely have 24v throughout, but i have some 12 volt ancilliary equipment i'd like to run by connecting them to ONE of the batteries.

[DamTriton]

Is it not possible to have two batteries operating in series for the winch but have a 12v alternator connected up to ONE of them to provide charge at 12v that is then spread over two batteries being in series?

Not sure if i'm describing it right.

two batteries in series for 24v

pos and neg from 12 volt alternator goes to pos and neg on ONE of those batteries providing charge. As battery charges it evens out its charge with the other battery by means of it being hooked together?

The reason i am asking this is because i am wondering if it will work the other way. I am building a hot rod truck that will most likely have 24v throughout, but i have some 12 volt ancilliary equipment i'd like to run by connecting them to ONE of the batteries.

Not a good idea to use only one battery if significant loads are likely to be applied with the alternator not running (motor off) as it leads to uneven charging of the batteries when the vehicle is started. The one that isn't used gets cooked while the used one is still taking bulk charge. Ultimately kills two batteries, one from overcharging and one from undercharging.

There are swichmode down converters available from 24V to 12V which are a better option (truck suppliers will have them, even Dick Smith sells them IIRC), or go the second alt and third battery route (12V).

[rockcrawler31]

Thanks kia, what kind of current can these devices handle?

What about my first question about charging a 24v set up with a 12v alternator? I'd like to run a 24v winch in the truck eventually and not have to run a second alt as well like the OP

[80's_delirious]

my 80series had two 12 volt 700CCA cranking batteries in it, it used 12volt for everything except the starter motor which was 24volt.

when you turn the key to 'start' it supplies 12volt to activate a solenoid which links the two 12volt batteries in series to supply 24volt to the starter motor

both batteries are charged by a standard 12volt alternator.

I would think similar could be done to supply 24volt to a winch

[DamTriton]

Thanks kia, what kind of current can these devices handle?

What about my first question about charging a 24v set up with a 12v alternator? I'd like to run a 24v winch in the truck eventually and not have to run a second alt as well like the OP

They are usually good for about 10-15 amps or so. generally made for modest radios/CD/media units (not 500 watt amps et al).


IIRC you already have 24V available from the truck's normal alternator and batteries (stated). You can use that for the 24V winch, maybe get the alternator beefed up.


"Add lightness and simplicate"

In general try to keep 12V stuff running of 12V alt/batt and 24V stuff of 24V alt/batt. Too many dramas trying to cross the paths when all you need in your case is a small 12V battery and a 12V alt hanging off the motor.

One more option is this From a Humvee. It presupposes a 24V (technically a 28V) ignition system to boot it, but it aint cheap.

[DamTriton]

my 80series had two 12 volt 700CCA cranking batteries in it, it used 12volt for everything except the starter motor which was 24volt.

when you turn the key to 'start' it supplies 12volt to activate a solenoid which links the two 12volt batteries in series to supply 24volt to the starter motor

both batteries are charged by a standard 12volt alternator.

I would think similar could be done to supply 24volt to a winch

Except you would not be charging the batteries at all (or only charging one of them) while winching...

For winching you would still need heavier duty solenoids for continuous current rather that the periodic 5 secs needed to start the vehicle.