Turbotalon22 (Customer) asked a question.

March 18, 2023 at 3:51 PM
Ptd24-20-vh vac transmitter and click plc.

I am trying to interface this sensor to a click to read vaccume down to -30 in/hg when i call up df6 in data view it is reading -14.5 just as is. If i suck on the hose i can see it moving toward the positive direction. Why would it not read 0 psi free air until a vac is pulled. Anyone have any suggestions? ​

  • 5 answers
  • 337 views

  • ADC Community_02 (Automationdirect.com)

    Since the scaling for analog doesn't support negative value as the max you will need to do this in Math instruction. Try the below formula where DF5 would be your channel 1 value. I did some testing and it appears to work correctly. 20mA = -14.5psi and 4mA= 0 psiimage.pngimage

    Expand Post
    Selected as Best

  • ADC Community_02 (Automationdirect.com)

    These sensors are 20 to 4 mA output.

    Your current settings 20mA= 0 psi and 4mA= -14.5 psi

    Your settings should be 20mA = -14.5psi and 4mA= 0 psi

  • Turbotalon22 (Customer)

    It will not work unless inise a positive number. ​

    • 20230320_225701

  • ADC Community_02 (Automationdirect.com)

    Since the scaling for analog doesn't support negative value as the max you will need to do this in Math instruction. Try the below formula where DF5 would be your channel 1 value. I did some testing and it appears to work correctly. 20mA = -14.5psi and 4mA= 0 psiimage.pngimage

    Expand Post
    Selected as Best

  • Turbotalon22 (Customer)

    Thank you very much for your help, i understand now! ​

 

Did this information resolve your issue?