24v winch power- auto sparky's?

[GUtripper]

I'll preface this by saying that I'm (sometimes) in the dark by auto electrics.

OK, recently had a 24v alternator fitted to the rig, supplying power to 2 x D31 optima's to run the winch motors.

Alternator is a new bosch 2456 internally regg'd 24v55a unit.

Have found that the alternator wont supply charge without a warning light.
Hooked a warning light on a simple loop and its a go, problem is when the motor is'nt running the light is on under the bonnet.... extended use (or un-use) would probably pop the 5w globe.
So options are to (1) to wire in a switch in the loop before the light, lift bonnet turn on switch before wheeling, or (2) wire it into the ignition circuit.

Option 2 makes more sense, but......
I wired a 12v 5w globe in line to the reg, but 12v globe/ig power doesnt supply enough oomph to the reg (24v remember) to get the alt to send charge to the batteries.

So was then thinking about a 12v switching, 24v power supply relay. 12v to fire off the ignition circuit, to effectively close a 24v loop. Apart from an albright solonoid or similar, is something like what i need available?

Or are there any other suggestions from the outers oracle?

[pcman]

a standard automotive 12v 30amp relay will work fine as your only switching a tiny 24v load for the last option you listed

[gudge]

Yep as pcman said. Switching a small 24v supply through a standard 12v relay will be fine. Its the way we have done it in all our trucks.

[mickyd555]

are you using this car to race? If so you need to put a battery isolator in place anyway so this should switch off the excitation light if you take the feed from the load side of the isolator.

If your not racing put a battery isolator in anyway and then no one can mess with your winch.

[toughnut]

Thats strange. When I wired up my warning light I had it running from a positive in the dash. Connected to the ciggy lighter circuit from memory then had the positive output/warning light output to the other side of the light. When the ignition was off there was no power to the light. Simple.

[GUtripper]

a standard automotive 12v 30amp relay will work fine as your only switching a tiny 24v load for the last option you listed

OK, ta. As I said its only a 24v 5w globe, can go a 2w if need be.
cheers

And yes, Isolator is next.