This example used a Hall Effect sensor to detect teeth on a steel gear. The CALC block is needed if your gear does not have exactly 60 teeth (60 pulses per revolution).
NOTE: Must use the isolated DI CHARM and must use an injected power terminal block.
See also:
https://emersonexchange365.com/search?q=pulse%20input#serpq=pulse%20input
https://emersonexchange365.com/search?q=RPM
https://emersonexchange365.com/search?q=hall%20effect
Trouble Reading RPM with and I.S. DI NAMUR CHARM
How do I configure a PIN (Pulse Input) function block for shaft RPM.
DeltaV-RPM-Hall-Sensor-Tach.pdf