Alternator warning lights

A standard modern alternator earths the lead from the bulb, so you can just move your existing lead over.

Mrcheerful

Excellent! Many thanks.

Ian

Beware though that modern alternators rely on the known resistance of the warning light to regulate the charge properly. Lucas alternators used a 2W bulb. This was a common size, so you should be OK, but it is worth checking when you swap the alternator.

Jim

That would be modern as in "rather old".

In my mind, anything not fitted with a dynamo is modern.

I take your point. But in this context, modern means with an integral regulator as opposed to the OP's external control box.

Jim

: > Excellent! Many thanks. : >

: Beware though that modern alternators rely on the known resistance of the : warning light to regulate the charge properly. Lucas alternators used a 2W : bulb. This was a common size, so you should be OK, but it is worth checking : when you swap the alternator.

Thank you!

Ian

The ACR series of alternators only use the warning light current to provide initial field excitation. Once charging, there are 3 diodes of the 9 in the diode pack that provide excitation and apply +12V onto the W/L terminal. The warning light is then connected across two terminals at +12V so does not light. The bulb does limit the intial field current but is not particularly critical. The alternator output is controled only by it's own regulator which is in the field return to earth circuit.

John