Thread: 24v and 12v?

Originally Posted by garrycol

My 101 is 24v originally running everything. The previous owners rigged up a 12v alternator as well as the original 24v alternator and the 12v charges secondary 12v battery/s.

I looked at all sorts of alternatives to get rid of this secondary system but as mentioned the 24v to 12v reducers are OK for small applications but even the largest ones really don't provide much juice. The same applies to the Redarc equalizers - to get anything of decent power is exceptionally expensive.

So I have stayed with my current system - plenty of power to run the truck, plenty of 12v power to run ancillaries including a winch. If starting batteries fail - you can always jump start yourself. The main downside is the space needed for the extra batteries.

Garry

Originally Posted by Brian Hjelm

You can use a 24v starter with a series/parallel switch and two 12v batteries. You use a 12v alternator and don't have to change the rest of the electrical system. Easy way to get one is from a truck wrecker. Commonly used on Cummins engines.

So Brian's suggestion is looking like the most attractive alternative to running dual charging/battery systems.

A simple way to dramatically reduce the 12V load on a dc to dc voltage converter or redrc charge equaliser, is to use 24V head/spot lights. Pairs of 12V globes can be wired in series to use in a 24V circuit, but downside is if one globe blows, the other won't get power.

Originally Posted by Brian Hjelm

You can use a 24v starter with a series/parallel switch and two 12v batteries. You use a 12v alternator and don't have to change the rest of the electrical system. Easy way to get one is from a truck wrecker. Commonly used on Cummins engines.

This is exactly the setup my rangie uses. But it's a 12v direct drive starter with 24v shoved up it.
Starts well but pulls 350-500 amps on 24v.

A lot of buses use them too.