Author Topic: Using a small motor as a dynamo.  (Read 2268 times)

Offline Don1966

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Re: Using a small motor as a dynamo.
« Reply #15 on: November 11, 2018, 10:58:47 PM »
Most LED's are killed if you expose them to more than 5V reverse voltage => AC is an absolute NO, NO  :zap:
and as mentioned you also need a series resistor and the size depends on voltage .... all in all - don't use LED's for testing - or perhaps - only use single LED's or better two anti-parallel connected with a series resistor.
You can put a diode reversed form the LED forward voltage to protect it using A/C with a ballast resistor if you use One LED or two LED back to back with opposite polarity !

Don

Offline steamer

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Re: Using a small motor as a dynamo.
« Reply #16 on: November 12, 2018, 10:16:12 AM »
There is a vast world of brushless motors on fhe market that should work just cine  both in runners and outrunners
"Mister M'Andrew, don't you think steam spoils romance at sea?"
Damned ijjit!

Online Alyn Foundry

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Re: Using a small motor as a dynamo.
« Reply #17 on: November 12, 2018, 10:24:41 AM »
Good morning Peter.

Glad to read you're going to have a " poke " around inside that casing, however....

Like Ian I'd strongly suggest an alternative, there's an amazing amount of permanent magnet motors fitted to motor cars. Having a PM field the armature will automatically start to deliver a voltage as soon as it begins rotating. Early Vauxhall cars had a large size motor for the radiator cooling fan.

You could then fabricate a suitable casing to " hide " the motor in. Obviously, patterns and a casting would be my suggestion!! :)

I've just remembered that Andy, Chipmaster, posted some photos on the Retlas thread, I'll link them as an edit.

Cheers Graham.

As promised....    http://www.modelenginemaker.com/index.php/topic,5720.msg141827.html#msg141827
« Last Edit: November 12, 2018, 10:38:00 AM by Alyn Foundry »

Offline Ian S C

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Re: Using a small motor as a dynamo.
« Reply #18 on: November 12, 2018, 12:01:39 PM »
Here is a small selection of my generating machinery. On the engine is a DC motor from a large printer, on the table left rear is a Sturmy Archer hub dynamo (AC) that I had set up for a wind mill. Right rear is the alternator from my post above, front left, the black tube hides a DC motor from a kitchen stick mixer, and the one on the right is a little DC motor from a HP printer.  You only get out what you put in, so it's the one with the best bearings that wins, all of these 5 end up the same with that or similar power motors.
« Last Edit: November 12, 2018, 12:09:22 PM by Ian S C »

Offline Roger B

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Re: Using a small motor as a dynamo.
« Reply #19 on: November 12, 2018, 06:30:39 PM »
Permanent magnet 'hobby' motors work well as dynamos for model engines (if you are into IC engines they can also be used as starter motors).
Best regards

Roger