Electronics, Lighting, & Gadgets - Lightspin electrics

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hairytoes
07-14-08, 08:17 AM
I've just acquired a 2ndhand lightspin dynamo.

Does anyone know how the electrics are controlled in this? From what I can work out, it is controlled to limit the AC output to 6.2V.

I'm thinking of feeding this to a full-wave rectifier and capacitor.

ModoVincere
07-14-08, 08:43 AM
I've just acquired a 2ndhand lightspin dynamo.

Does anyone know how the electrics are controlled in this? From what I can work out, it is controlled to limit the AC output to 6.2V.

I'm thinking of feeding this to a full-wave rectifier and capacitor.

Most dynamos are built to saturate at @6V AC. Some can generate more voltage, but most of them are limited by their design. In addition, good quality headlights come with zener diodes to also limit the current so you don't blow bulbs everytime you go too fast. That was a big problem with the older dynamos and lights.
hairytoes
07-14-08, 09:06 AM
I'm after specific information.

Lightspin's manufacturer specifically said NOT to use the dynamo with a zener diode. Unfortunately, since the company folded, all technical information has gone with them.

n4zou
07-14-08, 01:27 PM
A zener diode shorts current to ground to limit voltage. If you use a dynamo headlight with a zener diode it's is possible you could damage the electronics in the dynamo. A bridge rectifier does not short to ground so no damage will be done by using one with it. I sure wish I could get my hands on a lightspin dynamo!