DC Motors and speed control

[well-known_reindeer]

I have a 24 volt 350 watt scooter motor that need rewound. Specs say 3000rpm. Doe anyone know how many turns this motor would be?

 

[Minder]

The procedure when re-winding a motor is the count turns of each winding removed.
Probably not worth the effort for a small motor such as that, in light of motor replacement costs .

 

[well-known_reindeer]

I'm looking to increase to torque for what it's being used for

 

[Minder]

So you need a larger motor, rewinding is not going to achieve it!

 

[Alec_t]

Agreed. For a given Wattage motor there is a trade-off. You can only increase torque at the expense of rpm.
For any given motor there is a fixed space for the windings. Torque is proportional to the product of coil current and number of coil turns. So increasing the number of turns means using thinner wire to fit them into the space. But thinner wire necessitates lower current.

 

[CircutScoper]

I have a 24 volt 350 watt scooter motor that need rewound. Specs say 3000rpm. Doe anyone know how many turns this motor would be?

May I call you Rudolf?

As has already been said, Rudy, basic physics dictates a fundamental tradeoff for any given power rating between rpm and torque. Your 350W motor rating is equivalent to roughly 1/2 horsepower (actually 0.47). At 3000rpm, that works out to ~1.6 foot-pounds of torque. The only way to get more torque from 0.47hp is to reduce speed, and even if a slower scooter would be acceptable, you can't achieve that from rewinding alone.

Have you looked into changing the gearing ratio?

 

[Alec_t]

Have you looked into changing the gearing ratio?

That too has the torque/speed trade-off.

 

[CircutScoper]

That too has the torque/speed trade-off.

Of course. As said Torque = Power / Speed. At constant Power, Torque can only increase at the expense of reduced Speed.

The advantage of doing it by lowering the gear ratio is that it might be possible without re-engineering the whole powerplant.

 

[CircutScoper]

That too has the torque/speed trade-off.

On second thought, maybe best to forget the whole thing, given as little as we know about the "scooter" in question.

If Rudy WERE successful increasing motor torque, maybe that would cause the gears to strip, wheels to skid, or his antlers to fall off!

 

[davenn]

closed pending moving to its own thread

@well-known_reindeer Please dont hijack other people's threads, thanks