The light I'm using (inoled extreme) is very bright. It also must have an internal LED driver - a nice one, as..
this is what its back looks like.:
Both the headlight and my makeshift taillight (a oldish red Lumileds luxeon star LED) continue working (although not anywhere near as bright) for a while - several minutes at least- after the supply voltage (currently just a battery pack) stops.
Originally Posted by
unterhausen
the unloaded voltage of many hub dynos is reported to go up to 100v. So it's generally a bad idea to switch on electronics while riding.
But if you are driving a power led, most of them can take 1A which exceeds the current driving capacity of all of the hubs I'm familiar with. So it is unlikely to matter what the voltage gets to when driving an LED because the LED will drag down the voltage to the Vf of the LED. If powering something else, like a power supply, there may be an issue.
This is what I'm slightly worried about... just with a 12volt dynamo..
http://www.peterwhitecycles.com/inoled.asp > "inoguard"
Or here:
http://www.inoled.de/en/accessories/inoguard
BTW, this light combo is very nice.. - my old light was a dynamo light but it used an incandescent, and that was nothing like this in terms of brightness, and when i stopped at traffic lights, it went out completely.
If I'm not adding additional electronics, there really is no reason to get a 12v dynamo.. maybe I'll just get a 6v one..