Hand crank 48V/24V generator

[aboico1]

hi, i am looking for a hand crank generator of 48/24 volts.
the current must be around 3 amps.
any suggestions?
i have a 12V generator, maybe it is possible to convert it to 24/48?

 

[Nigel Goodwin]

Wind it faster - voltage is related to speed.

However 48V at 3A is 144watts - rather excessive for a hand cranked generator? - what are you trying to do?.

It's generally accepted that an averagely fit man con maintain 60W from a pedal driven generator, for short peaks of 100W.

 

[aboico1]

the generator i have is stable at 12V. so winding it faster will not change teh output.
ok, so maybe 48V with 1amp, or 24V with 2 or 1.5 amp.
i am trying to light a floroucent lamp.
i have a 24V ballast. i wish to create a 48V ballast.
For my project i just want to adjust my hand crank generator

 

[dr pepper]

You'd have strong wrists after using that for a while 100w takes a bit of pulling, riding a pushbike only uses around 300.
You might be better making something using a 12v gen and an electronic ballast, there are plenty of 12v to fluo tube drivers on google.
For the gen a modded car heater or window motor.

 

[aboico1]

so, after a lot of thinking i have decided to convert my12V 1.5A generator to 24V 0.75A.
to do that, i need only to replace the voltage regulator? now i have the LM2596 in the generator.
any suggestions?

 

[()blivion]

Just some simple things.

Schematic? Pictures? Is it a dynamo or is it a self starting alternator? Does it have a gear box? Will it blend?

Too bad you missed my Ebay auction by about 6 months. I had four 150+ volt dynamo's from some really old military phones. Had internal centrifugal switches so they would only engage when the generator was spinning fast enough to make ~50 volts. With a post converter/regulator they could make any voltage you wanted. But I sold them all already

Edit: The LM2596 comes in fixed voltages. Yours is likely 12V. Well, If you lift the Feedback pin (pin 4), and hook a voltage divider up between the Vout and ground, then feed the middle of the divider to said lifted pin, you can make any voltage you want. For 24v, it would be a 1:1 ratio divider. Or 1/2 ratio if you prefer.

Edit 2: Or if you REALLY prefer... here is a picture instead.

View attachment 66349

 

[Grossel]

Hi.

I did once managet to get one 24V 3-phase generator, hand winded.

It came from an emergency radio too old (for use on new communication systems) from a ship. Got it from a nice fisherman.

Nice to have with all kind of rare expreiences

So If you know a captain on an old boat he maybe have one. Nb - do ask if it's critical in an emergency situation. Such a sender might be in use in your country.