Speed info from incremental encoder.

Is there something specific you want to know, or do? Is it for control, or just monitoring?

Not sure how much you know about encoders so far, but A and B are typically i" in Quadrature" meaning that the are out of phase by 90 Electrical Degrees. The phase shift allows you to determine the direction of the encoder by reading which state comes high after both are low.

If you are in need of determining RPM from the input frequency, The formula is:

RPM = (Freq. X 60)/ Line Count.

You can use the index channel ( typically called I, Z, or Marker) to home the encoder.

I am not too familiar with the capabilities of your PLC, but You will also want to make sure you don't overclock the input. You can calculate the max freq. by rearranging the formula:

Freq = (RPM X Line Count)/60

Let me know if you have any other questions.

Jim Miller

Application Engineer

Quantum Devices Inc.

jmiller@quantumdev.com

Thanks for your help on this,I appreciate it.

Jakbeuk