sha102

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Posts posted by sha102

  1. Posted

    Thanks a lot for your responses. 

    • I thought the digital inputs have internal pull up or is that installed externally?
    • About wiring, Please see attached image. My understanding is that R3 is internal and I would like to find the value of that.
    • I looked at Siemens S7 datasheet. Based on the DO numbers,  R3 would be 8k. Voltage simulations shows PLC input is not getting close to 0 V in low state. I am concerned that the threshold wont be met and be detected by the PLC as a low.

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  2. Posted

    hello everyone ,

    I am involved in the development of an industrial  product. It has a 24 V On / OFF  output signal which will be read by a PLC digital input. It could be Allen Bradley / Siemens .  Can anyone tell me what would be the approximate values of the internal pull ups and pull downs? where can i find this? Thank you for all the help.

     Regards

    Sha

     

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