Hi!

New here.

I’m installing a busch & muller led headlight on my old bike, powered by an old bottle dynamo.
Did a quick test after blindly guessing about the connectors on the dynamo and the light is working just fine. But I’m not certain I have the wiring right and I don’t want to fry the headlight, the connectors on the dynamo are marked only B and S. A quick search told me that it stands for headlight (B) and taillight (S). There was no indication about polarity or if the chassi and mount act as ”ground”.

Like I mentioned the light is working as I have it set up, I connected B to plus and S to minus I think for a quick test. (before googling..)

Can someone help me illuminate (no pun intended) the matter? The headlight has no ground connection at all as tested. Why would the dynamo have one connection for the headlight and one for the taillight?

Thank you
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