Motor RPM

[Gonkulor]

Sheesh, I messed up my first try at this. Anyway. copy paste.

Here is something I want but not sure if it's possible.

Electric motor RPM meter. 93 Marathon series. I got the computer for arduino if needed but a simpler output from the moter would be even better. I'm going to redo the motor this winter and I would like to have a sensor added when I rebuild it and have it when I do the rebuild in case weight and balance is a factor. Not sure if it's even possible or I should try something that is being tested?

It's all about electric power these days so I have to ask if something is possible and maybe if I can even help produce.

[JohnnieB]

I'm not sure if a sensor assembly from a PDS motor could be mounted on the back end of a series motor, but it might be food for thought.

Basically it is a disk with eight magnets that screws into the motor shaft and a stationary pick-up coil the mounts in close proximity to it, so you get 8 pulses per motor revolution.

I've been kicking around the thought of using the output to feed a tach if and when I go to an aftermarket controller.

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Weight and balance could be an issue in adding a magnet to the shaft.
Perhaps an optical sensor might work.

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Another thought is to measure wheel RPM and multiply by the differential ratio.