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  • #16
    I got it, and the winner is :ADC_TAG_02. It didn't worked at first because I forgot to clear the PLC memory from the previous program. I tried it again and worked like a charm.. Interval config is the way to go .

    Thanks a Lot to all.


    • #17
      Good Morning,

      I have the Interval config running Ok, this is the setup recommended by ADC_TAG_02, but if the machine is running and it stops abruptly the speed counter stays at the speed it was when it stopped . There may be something I can do in the interrupt program to make dd1 go to 0 or something else. Anyone can help me with this?


      • #18
        Have an input move a 0 whenever it is in one position, closed or open, for longer than XX seconds..


        • #19
          Use a free-running timer in your main program. Decide what does "zero velocity" mean to you, then set the timer accordingly. This is setup that if a pulse is not received in 2 seconds, then the RPM calculation is set to zero. In the interrupt routine, each time a new measurement is completed zero the Timer value to prevent zero speed detection.
          Attached Files


          • #20
            Thank you ADC that's what I did to make it work. I thought something better could have be done. thanks again


            • #21
              Originally posted by RogerR View Post
              To get a time base between CT1 pulses, maybe this timer value store line would work.
              It will store the time between each pulse and reset the timer value to zero.
              This stored value could be converted to an engineering unit like RPM.
              C1 in the picture should be from CT1.

              Click image for larger version Name:	Timer Val Store.jpg Views:	0 Size:	42.5 KB ID:	128892
              Hey Roger, I have another pulse that I need to setup, but this time is not connected to the CPU directly so I don't have high speed counter. I have your recommended line done but as I said before it runs backwards. Is there a way to make this right. I need the fastest the pulse the higher the number.

              Thanks in advance.


              • #22
                To invert the direction of the numeric change you could use another tag at the end of a math expression.

                60000 - (60000/DS1) = DS2
                60000 -DS1 = DS2

                This will make DS2 higher as the frequency increases as DS1 frequency decreases.

                The new tag would still have to be modified to an engineering unit as before.
                It may also need to be scaled with a non zero starting point.