JB2020 (Customer) asked a question.

Using +24V for the STO or a Separate Supply

I have always used the +24V STO Terminal and ran a wire from it to a safety relay and back t the STO1 and STO2 Terminals. The manual shows using an external supply which utilizes the SCM Terminal and doesn't use the +24V Terminal. Is this an either/or situation or is one option better than the other?


  • ADC_Drives_Motors_PE (AutomationDirect)

    Good afternoon, Appendix E, page 2 has the STO wiring descriptions. The 24+ vdc is only used to disable the STO function.

     

    The TUV validated configuration for the STO function is to wire the drive to a Safety PLC or Safety Relay it as shown in the diagram. Any other wiring configurations will not meet the TUV STO approval for this drive.

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  • JB2020 (Customer)

    @ADC Community_02 (Automationdirect.com)​ Would you have any input on this? I posted this 22 hrs ago and haven't got any response yet.

    • ADC Community_02 (Automationdirect.com)

      Which product(s) are you referencing? Not familiar with STO but can reach out to someone who does.

      • JB2020 (Customer)

        GS23-43P0 VFDs. I posted this in the drives section so I figured it was known.

  • ADC_Drives_Motors_PE (AutomationDirect)

    Good afternoon, Appendix E, page 2 has the STO wiring descriptions. The 24+ vdc is only used to disable the STO function.

     

    The TUV validated configuration for the STO function is to wire the drive to a Safety PLC or Safety Relay it as shown in the diagram. Any other wiring configurations will not meet the TUV STO approval for this drive.

    Selected as Best
    • JB2020 (Customer)

      Thank You for the response!