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General => Technical support => Topic started by: bilt2spd on September 22, 2004, 06:12:03 PM

Title: RPM switch
Post by: bilt2spd on September 22, 2004, 06:12:03 PM

Is it possible to use the ladder logic in a PLC to act as a RPM activated switch? I assume it would be some type of counter per a time interval. Thanks!

Title: Re:RPM switch
Post by: support on September 25, 2004, 06:16:51 PM

If you want to activitate a switch when the RPM reaches a certain value, then you can use the PULSEFREQUENCY function to measure the incoming pulse rate and make a decision:

E.g. IF PULSEFREQUENCY(1) > 1000 THEN
           SETIO OUT1
       ELS
           CLRIO OUT1
      ENDIF

This is the unique capability of M-series PLC's "Ladder+ BASIC" command and not available to ladder logic only PLCs such as the H-series or E10 and certainly not applicable to other makes of PLC.