CALCULATING RPM

Dear all,
In one of the our projects, our client want to synchronize two motors with together.

Each motor has one VFD drive and one pulse encoder (1000).

At the first, I want to read pulse encoder’s data (Motor No.1) by S7-1200. After that I want to convert (Unscale) RPM’s of first motor to pulse for command to second motor.
These are my questions:

1. How can I calculate motor’s speed (RPM-round per minute)?

2. How can I unscale RPM to pulse?

Do you have any solution for this project?

I’m looking forward for your reply.

Best regards,

HWF

i need sampel progeram for calculting in s7-1200 .
with encoder 1000 pulse

best wish for you