Shelly 1PM turning OFF when SW voltage is 0 - is it possible?

There are 9 replies in this Thread which was already clicked 135 times. The last Post () by thgoebel.

  • Is there a possibility or create a scene which will turn off Shelly 1PM device (and as consequence turn off water pump connected to Shelly 1PM) when voltage on SW connector is 0? And vice versa, when Shelly 1PM detects voltage on SW connector, to turn on Shelly and turn on connected water pump?

    Reason is because I can only turn on or off pump with Shelly Cloud app but I need also that pump is turned off when my heat pump (Daikin Altherma 3) is turned off (as it worked before Shelly 1PM installation).

    Thanks in advance.

  • Shelly 1PM relay is switched on, if current flows from terminal SW to terminal L. This means, if a contact is closed, which is arranged between terminal SW and L, Shelly relay is activated.

    Lesson learned: Shelly isn’t activated by voltage, but by current!


    Next lesson: The Shelly input may be inverted by setting “Reverse Input” in menu “Button Type”. This means, all the conclusions given in first section has to be inverted.


    Now you’ll have to revise your needs and make a new plan!

    „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)

  • Thanks. The problem is that I don't have classic switch with two wires which need to be connected to SW and L. Meaning, my heat pump (as power source) has "switch" inside it and I connected live line (brown wire) from heat pump switch to SW terminal on Shelly. Water pump is connected to Shelly "O" and L1 to line and N to neutral. L connector on Shelly is not connected.

    So, when heat pump is disconnected, there is no voltage on SW connector but water pump is still running (until I put it off via application) and all connectors ("O" and L1) have voltage.

    I supposed that Shelly 1PM can be turned off or on dependent on voltage on SW connector with scenes. There is scene "when input state is off", so I assumed it is connected with SW connector.

    I am not sure how to have old on-off functionality and to measure power on my water pump or is it even possible?

    Scene "when input state is off" is for what? When this condition is met?

    Thanks,

  • Ok. Issue is clear: You want to activate a Shelly by a switch/consumer unit. In this case, you’ll have to switch the Shelly with neutral potential, which is given by the motor coil of the heat pump. Thus, activation of Shelly via live potential at terminal SW has to be inhibited, cause otherwise Shelly would be permanently activated (by neutral AND live potential). This inhibition can be done by a resistor of about 500kΩ to 1MΩ in series to the SW terminal. How this may be arranged is described here: Click! (Thread is unfortunately in German language. But you may use a translation app,,,)

    „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)

  • Basically, I want that my Shelly 1PM is always ON (because it is also measuring temperature via temperature add-on) and to activate "O" only (water pump is connected to "O") when my consumer unit gives signal (voltage) which is connected to SW. Or vice versa, when there is no voltage/signal on SW from my consumer unit, this triggers pump tu turn off on "O" connector. Is this even possible?


    Basically, I connected switch and Shelly 1PM as in this video:

    How to automate your lights using a Shelly 1PM
    In this video I'm showing how to automate a light bulb using a Shelly 1PM.Shelly 1PM Product Page: https://shelly.cloud/products/shelly-1pm-smart-home-automa...
    www.youtube.com


    where switch on the video is replaced by switch in my consumer unit. Wiring is the same. And it is working in video but does not work on my place.

    Edited once, last by Stile ().

  • I assume Shelly 1 PM is measuring temperature via an Add-On independent of its switch status. Keeping this in mind, the Shelly relay may be activated (a) the resistor at terminal SW and (b) the setting of “reverse input”,

    „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)

  • Update: if I connect real switch on SW pin instead of consumer unit switch, it is working correctly. When real switch is off, water pump is off. I don't have a clue why it is not working when I connect consumer unit switch on SW pin. Any ideas?

  • You just got one hint in post #4

    Another hint is to use an intermediate relay between pump and Shelly SW input: The coil of the relay is connected in parallel to the heater pump, the relay contact (normally open) between terminal SW and L of Shelly. Obviously, you’re preferring the expensive solutions…

    „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)

  • Thanks, that's great. So options are to use resistor on SW or relay between consumer unit and Shelly?

    But please, if you can explain more in details, why it is working when I test with real switch and it is not working with consumer unit motherboard switch? Principle is the same: voltage exists on SW or not. Or maybe Shelly is too sensitive and don't react somehow on consumer unit switch?

    And relay will react on consumer unit switch?

    I would like to know electrical reason behind and thank you in advance for detailed explanation. I translated the post about resistor that you linked and connection is clear but I didn't understand reasonings behind. Please explain, I will greatly appreciate it.

  • The reason is Shelly SW input is activated both with neutral AND live potential! Please let an app translate the link given in post #4 to get more and better details.

    „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)