Alternator problems

[99176]

I've got my hands on a 'Powerlite' alternator and now have a problem that is no doubt simple for a sparky to suss.
The main charging lead connects to a 6mm pole connector on the alternator.
The warning lamp lead is connected to the top part of a 'T' type connector.
The upright of this 'T' is connected to a 12v supply at solenoid.
Now my battery drains overnight, and a multimeter tells me the cause is the 12v connection.
What, if anything, goes to this third connector ?

[Clive]

I think the 12v supply should be ignition controlled? but it sounds like it is.
I have a simple understanding that it turns the alternator on. It is how I have my little denso alternator wired, and no issues. Unless the alternator is faulty?

[99176]

Hi Clive,
    Was thinking along those lines.
Nice to have some backup.
Haven't seen you since Goodwood, how's the Zetec coming along /

[Clive]

veeeeery sloooowly :B
on the plus side, the front brakes are looking good now. So it is just to fit the tub, bonnet, engine, electrics and lots of other stuff. And did I mention a respray? got the paint though :)

maybe doing the Donnington day in October, but it is just a few days before Gills birthday. So it could be her birthday surprise :)

[junkuser]

Have you tried putting a meter from output terminal to body of the alternator to check resistance each way to see if a diode has failed?

[99176]

Seems to be sorted with 12v ign feed.
Cheers