24v alternator info

[ifslux]

Hi im after some info or even a wiring digram on how to hook up a 24v alternator on my comp truck. i know how to wire the batterys but not sure about the rest of the wiring. does it need a turn on wire ? any help would be great.

cheers steve.

[mickyd555]

yes, you need an excitation wire.

[GUtripper]

Had the same issue when connecting up 24v about 18 months ago.
Two batteries in series to make 24v on a closed/separate loop to the 24v alternator.
The trigger/hot wire to activate or turn on the charging needs to be triggered by the normal 12v circuit without connecting the two circuits and causing grief ( or a fire).

I used a 30a relay.... Wire it into the 12v ignition circuit on the switching side so when the engine is running it 'turns on' the alternator hot wire and closes the circuit. I wired in a 24v light bulb, so much like a normal alternator warning light that will illuminate if there is alternator or charge problems.

I think I've explained that ok...

[fazza81]

Some 24v alts are self excite and do not requier lights etc.
or
You can get exicter resistors which bolt to the back of the alt and excite that way.

[ifslux]

Cheers for the info everyone. After Many hours of serching I found a write up using the realay idea. I haven't got around to doing it yet but hopefully it works out ok.

[-Scott-]

Cheers for the info everyone. After Many hours of serching I found a write up using the realay idea. I haven't got around to doing it yet but hopefully it works out ok.

Any chance you could post a link for the rest of us?

[ifslux]

I'll see if I can find it again.

[mickyd555]

I had the excitation wire on the load side of the 24v isolator. That way I had a visual check that it was on(light in cab) before starting the car. Light went off when the engine was running so I knew it was charging. You could also use the relay but take the supply from load side of the isolator for a check its on.