4-20 Sink or source or both?

Regarding the 4-channel Mirpro, I see two different wiring diagrams for the output. Which one is correct? Do I need an external power supply or does the MirPRO power the output?

Also, I see a warning sticker on the input terminals. Can I use a signal that is powered by the transmitter (sourcing) or does it need to be passive (sinking)?

Hi @antonloof
Depending on how the PLC manages the 4-20mA input, you can use either a loop-powered or externally powered sensor:

  • Some PLCs’ Input 4-20mA has a built-in current source that can supply power directly to the 4-20mA loop.
  • Some PLCs’ Input 4-20mA require an external power supply to provide the current for the 4-20mA loop.

Respect input sensor, you don’t need to provide external loop power for the sensors connected to the inputs (as shown in the diagram).

Let us know if you have any questions,
Eduardo M.

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