Having 12v and 24v in the car

[MightyMouse]

Originally Posted by Wazza D

You can then use that space under the hood to cook pies instead of your battery.

Now that is the best reason for a battery relocation that I've heard of to date, and it almost certainly would work.

[Lim@]

Originally Posted by layback40

Does the OP have much experience with this sort of thing or is the thread an internet dream?

I'm a sparky and pretty confident with the parts lying in front of me could have it all set up within the day.

but ive never used dc to dc transformers to charge batteries, i assume it shouldnt be an issue though.

While i may be able to do the starter as well, im planning on having everything that originally runs 12v staying as 12v. the car will not actually see any difference, im not combining 12v and 24v in the one car, everything will still be 12v, but i want to run a closed loop circuit just for auxillery equip such as winch, fridge and light bars. i will just need to buzz out the lightbars and make sure the body of the light bar isn't joined to ground internally or else i will lose my closed loop.

so this is different to landcruiser etc that use the same 2 12v batteries normally in parrallel and use a series relay to create 24v for the starter motor only off the same batteries. my 12v battery will only do 12v stuff, and my 2 batteries making the 24v will only do 24v stuff.

mighty mouse made a fair point in whats the point for the other stuff other than winch, i completely agree but i would only run the lightbars etc off the 24v system so i only have the standard car electrics draining the starting battery. otherwise i dont care

[Wazza D]

In that case I guess you would set it up similar to the jump start system I mentioned?
You would just have your ancillary equipment running off it rather than a broken down machine.
I would still be nervous about dicking around on vehicles with sensitive electronics on them.

[MightyMouse]

You could be actually making thing slightly worse for the light bar..... the LED's are electronically current regulated, so by increasing the supply voltage your potentially increasing the dissipation of the regulator system.

Most are multi voltage ( check first ), so no harm will be done...... but your not really achieving much as their current draw is pretty modest and pretty constant regardless of supply voltage. Its not just an Ohms law thing with solid state devices.

You could easily check it out with you light bar.... measure its current draw at 12V then at 24v... if there's a worthwhile drop then perhaps... but it still seems like a lot of effort for little gain.

When you start drawing hundreds of Amps there certainly are advantages to be had but most of the time if losses are a concern just run a larger CSA cable.