I have a Busch & Muller Lumotec IQ2 Luxus U in my 'that'll be useful one day' box that's be sat there for ten years that I want to sell, problem is I don't have a dynamo to wire it into to test it to see if it still works. Just connect it to a 6v battery I here you say, but can you do that? Batteries produce DC whereas dynamos AC.
If that's okay, fine problem solved, if not how can I test it?
Dynamo Light
Re: Dynamo Light
The headlamp should light up if it is connected to a 6v DC battery. It might not work at full power though, and the stand light may charge from only the +ve or -ve part of the AC so you may have to try swapping the battery connections around to test that part of it. Ditto any other fancy features the light may have.
Re: Dynamo Light
if you could lay hands on a bottle dynamo that'd do the trick.
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Re: Dynamo Light
If you have any MR16 domestic lights then these are rated at 3watts 12volts. Plug your dynamo light into one of these light fittings which usually come with a step down transformer would give you a low voltage ac supply. I dont think the 12V ac supply voltage would cause an issue for a short term check but see what others say too.
Peugeot 531 pro, Dawes Discovery Tandem, Dawes Kingpin X2, Raleigh 20 stowaway, 1965 Moulton deluxe, Falcon K2 MTB dropped bar tourer, Longstaff trike conversion on a Giant XTC 840, Apollo transition. 
Re: Dynamo Light
I think it will depend if the light fitting has a LED driver which limits the current in the same manner as the dynamo would normally do. Dynamo lights require 0.5A (or 0.4A for the front light). 3W at 12V corresponds to a current of 0.25A which might work with the headlamp, but again only if the light fitting has a current-limiting LED driver.
If the light fitting simply provides a 12V voltage source and isn't current limited then the current will be limited only by the impedance of the headlamp which is normally about 15Ω when driven by the dynamo (https://swhs.home.xs4all.nl/fiets/tests ... t=15%CE%A9). Assuming the same impedance at higher currents (which it might not be) the resulting current will be ~0.8A which might be too much for the headlamp, even if it has protection circuitry.
Also, don't confuse the MR16 G5.3 light fitting which a G10 light fitting which runs directly from mains 230V. They do use different connections at the bulb and are distinguishable but if not, then plugging your dynamo into mains would be disastrous, even fatal.
Edit - TL,DR: I guess what I'm trying to say is be very careful if you're going to use a MR16 light fitting as a surrogate dynamo. I wouldn't advise it, if you don't understand electrical/electronic circuitry and stuff.
If the light fitting simply provides a 12V voltage source and isn't current limited then the current will be limited only by the impedance of the headlamp which is normally about 15Ω when driven by the dynamo (https://swhs.home.xs4all.nl/fiets/tests ... t=15%CE%A9). Assuming the same impedance at higher currents (which it might not be) the resulting current will be ~0.8A which might be too much for the headlamp, even if it has protection circuitry.
Also, don't confuse the MR16 G5.3 light fitting which a G10 light fitting which runs directly from mains 230V. They do use different connections at the bulb and are distinguishable but if not, then plugging your dynamo into mains would be disastrous, even fatal.
Edit - TL,DR: I guess what I'm trying to say is be very careful if you're going to use a MR16 light fitting as a surrogate dynamo. I wouldn't advise it, if you don't understand electrical/electronic circuitry and stuff.
Re: Dynamo Light
Says it shouldn't be done here:
https://www.starbike.com/manuals/bumm-179-manual.pdf
Probably means you'd have to be very careful. Over-current risk would be high without some form of current limiting, or no light at all if from too low a voltage. Maybe a resistor would be enough.
https://www.starbike.com/manuals/bumm-179-manual.pdf
Probably means you'd have to be very careful. Over-current risk would be high without some form of current limiting, or no light at all if from too low a voltage. Maybe a resistor would be enough.
