I have a question concerning the rectifier wiring with warning light.

I have an alternator switch. The alternator switch is connected to a relais what is switching the R/+B/C leads. Because of this installation the warning light is only turning on, when the alternator switch is on and the engine out. But I would like to have the warning light also to be on if the alternator switch is off. As the L lead is pulled to minus when the rectifier is not charging it seems the rectifier needs power to do so. 

I assume I have to connect the C Lead to the battery (this seems to be the power lead for the rectifier) and it should not be switched by the alternator relais to have the warning light also on if the alternator switch is off.

Can anybody give me advice how they did the wiring when using an alternator switch and charging warning light?

Thanks in advance,


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If the C lead is kept hot, it will drain battery in 2 weeks. Don't do that. Keep the c lead switched with key.

Hi Bob, yes that's clear.

The C Lead is now switched by the master switch. So if I turn on the master, the alternator warning light comes on because the rectifier is powered, The light remains on when I switch on the alternator switch. The light goes out when engine is started and alternator switch is on -> loading the battery. So this setup is perfect now for me. The Alternator warning light warns in case of no loading or alternator switch off.


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