Outer Limits 4x4 Board

Hi All
I was wondering if it was possible to run my driving lights at 24v whilst keeping the rest at the original 12v. I have dual batteries and the lights are rigs lights so they can take 24v globes.
I want to do this to halve the amount of current drawn.
Cheers Andrew

No you can't.

Jason

bugger, not even with some big diodes to stop current turning the entire system to 24v??? i'll ask my boss he'll figure it out 4 me
Would be handy only drawing 50amps instead of the 100 i draw at the moment

Big Red Toy wrote:Would be handy only drawing 50amps instead of the 100 i draw at the moment

So you've got around 1200 Watts of lights on your rig!?

Well i have
4 * 130watt lights on roof
100/130w headlights * 2
2 * 130w rig lights on bar & 2 smaller 65w on bar

so thats
2 x 130
4 x 130
2 x 130
2x 65
= 1170watts/ 12volts
=97.5 amps

Thats heaps from a 50amp alternator.

Or it could be 1170watts / 24 volts = 48.75 amps

Which is heaps better.

What about getting a 24v alternator to run headlights???

The need 4 so many lights is : I"M AFRAID OF THE DARK!!!

You'd still need a battery (or two for 24V) to go with the 24V alternator.

I'd suggest you eat more carrots and lose a few lights.

Stick with 12V, it's easier. Just upgrade your alternator and fit the biggest battery you can.

yeah, i thought that would be the go, oh well, i'll think about what i can do.
thanks for your help.

if you hate the dark that much, invest in a set of HID lights. not cheap but will cost you less in the long run over trying to set up a custom 12/24 volt system and they last forever whereas high wattage halogens burn up pretty quick by comparison especially in 4x4 applications where they get a lot of vibration. HID's don't have a filament at all so there is nothing to burn or break.

you might also want to try putting an ammeter in series with your battery/alternator and lights, your lights probably only draw about 70 - 80% of their rated power/current - unless your charge light comes on (and/or your voltmeter drops below about 12.5v) your alternator is coping with the load as is.

Doesn't matter if you halve the ampage really, the wattage or power used still remains the same. Probably easiest just to convert the whole car to 24v, witha 24v alternator, you could keep the starter / wiper motor and some other stuff at 12v with some tricky wiring.

Rainbow Warrior wrote:Doesn't matter if you halve the ampage really, the wattage or power used still remains the same. Probably easiest just to convert the whole car to 24v, witha 24v alternator, you could keep the starter / wiper motor and some other stuff at 12v with some tricky wiring.

Power loss in the wiring is related to the square of the current. Halve the current thru' the wire, and the power loss in the wire is reduced by 75%.

Higher voltage is always more efficient for power transmission. The only real decision to make is about the cost - is it worth it?

I think the HID suggestion looks good to me - more light for less power

Scott

NJ SWB wrote:

Rainbow Warrior wrote:Doesn't matter if you halve the ampage really, the wattage or power used still remains the same. Probably easiest just to convert the whole car to 24v, witha 24v alternator, you could keep the starter / wiper motor and some other stuff at 12v with some tricky wiring.

Power loss in the wiring is related to the square of the current. Halve the current thru' the wire, and the power loss in the wire is reduced by 75%.

Higher voltage is always more efficient for power transmission. The only real decision to make is about the cost - is it worth it?

I think the HID suggestion looks good to me - more light for less power

Scott

I realise voltage drop can be an issue, but you can always run bigger wires.