Alternator wiring

[Rootsey1]

hi. Would anyone know which one of the 2 wires that goes to the alternator is the one that energises the rotor. Is it the thick or slightly thinner one.

 

[frank]

wire a 5w bulb to +12v and see which one kicks it in

 

[Rootsey1]

Hi Frank. I've put a meter on it and the thick one has a permanent 12v. When running the slightly smaller one didn't have 12v. I think it was about 6v

 

[frank]

the one you want is connected to the telltale bulb in the dash eh

 

[Rootsey1]

Brilliant thanks frank.

 

[frank]

and the current draw from that bulb is enough to kick the field coils into action

 

[Rootsey1]

We want to stop the alternator charging during a race but want it to charge while running round the pits and waiting to race. Am I right in thinking we can do this by adding a switch to this wire which we can flick over just before the race.

 

[frank]

i think you will need to turn the engine off before switching the telltale light off mate

 

[Rootsey1]

Was hoping to switching the thick wire that goes to the same terminal as the tell tail light would stop it charging. Was hoping this would make the light come on so he would known what's it's doing. I suppose the thing to do it try it.