How to connect a Photoelectric Sensor to the add-on?

  • Hello all ,

    I have Shelly 2PM plus with a add-on.

    The Shelly 2Pm plus and add-on are connected to 24V to controll a linear actuator.

    I want to attach a Photoelectric Sensor , but I don't know how to connect the Photoelectric Sensor to the add-on , can someone share some light?

    It is this Photoelectric Sensor:

    PNP - E3Z-R81

    2023-08-26 20_02_54-E3Z-R81 2M _ OMRON Industrial Automation.jpg

    I have 3 wires , Brown - black - blue

    Many thanks for your help ,

    Cor

  • Hello Cor,

    As far as I know, you cannot connect directly the Photoelectric Sensor to the digital input of the Shelly 2PM Plus Add-on, because the digital input switches into the minus (gnd). The Photoelectric Sensor you want to use switches into the plus.

    - The brown wire is the plus (power supply) 24V dc of the Sensor.

    - The blue wire is the minus (power supply) 0V dc of the Sensor.

    - The black wire is the switching wire that you could connect to an input on, for example, the Shelly Plus I4DC, the only question is whether the Photoelectric Sensor output does not need a little load to switch properly.

    What could possibly be a solution, to have the sensor switch a relay and offer the potential free contact of the relay to the digital input (and gnd) of the add-on, that will work.

    Good luck with your project.

  • A simple pull down resistor (4,7 to 10kΩ) does the job…

    „Habt Geduld. Alle Dinge sind schwierig, bevor sie einfach werden!“ (aus Frankreich)

    „Nothing in life is to be feared, it is only to be understood.“ (Marie Curie, 1867-1934)

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    (Aus „Besuch aus Weimar“ von Gert Heidenreich, Schriftsteller, *1944 in Eberswalde)