Help calculating how fast an encoder is sending pulses

Thread Starter


Joined Jun 11, 2020
Hi all,

I am trying to get clarification on my calculations because they don't feel correct. I want to calculate how fast my encoder is pulsing.

For the info. I know my encoders resolutions 200 pulses per revolution and that my wheels circumference is exactly 1 foot.

I also know that the average speed is about 115 rpm. or 1.9rps. (lets round it up to 2 for sake of ease)
Here's my work:

2 rps * 200ppr =400 pulses per second. I then invert this to get how many seconds between readings. 1/400 = 0.0025 = 2.5ms/pulse.

So according to this I pulse every 2.5ms which will be sent to a PLC to be read. I believe this is fine?

I think ive just been staring at this too long! Thanks!


Joined Jan 6, 2004
The radius has no part in your calculation.
You are dealing with angular speed.

BTW, don't you have a way to measure the frequency of the outcoming pulses to see how far / close is your calculation?

400 pulses in 1 second.
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