inductive proximity sensors resolution

[akshay985]

what is the resolution of a proximity sensor?

i want to measure the variable speed of a motor

 

[BradtheRad]

You can try putting a coil next to the motor. Or wrap a few turns of wire around the housing.

This may pick up enough signal to read on an oscilloscope.

It may show your drive pulses. With a DC motor it may show commutation on-off.

Can't predict how easy it will be to measure speed.

 

[FvM]

The question isn't quite clear. The standard method to measure speed with a proximity sensor is placing a toothed wheel at the motor shaft and count pulses, respectively use a f/V converter to get an analog quantity. In this setup, you would ask for switching speed and possibly detection distance of the proximity sensor rather than resolution.

But perhaps, you can clarify your reuqirements?