Switching Lights by relais



  • OK, I looked in to the UniPi to use it as a home automation controller for my lights in the house.
    Now I’m not sure if I can do what I’m looking for, so if anyone can help me on my way that would be great!

    At the moment my lights are switched by Hager EPN513 DIN Bistable or Latching relays (we call them Teleruptors).
    [attachment=0:enkbl4cg]Knipsel2.JPG[/attachment:enkbl4cg]

    This relays switches 240 Volts to my lamps by connecting 24 Volts buttons to it. So when I press a button on the wall it sends 24 Volts to the relay and the relays switches the 240 Volt.
    [attachment=1:enkbl4cg]Knipsel.JPG[/attachment:enkbl4cg]

    Now my question is, how can I use the unipi to switch my relays and still keep the 24 volt buttons, AND I need to know the state of the relays. Say I switch the lamp on with the UniPi and back out with the button. My software needs to know what happened there …

    I was thinking to connect my buttons to the digital inputs of the Unipi (not sure if 24 Volts is going to work) and connect my DIN relays to the relays on the UniPi. So than I can digitally turn my lights on/off with the UniPi and still use my buttons, sins they also switch the UniPi.
    Will this setup work?

    If this works there is only 1 problem … The UniPi becomes the single point of failure. Not that I don’t trust the quality of the UniPi, but things just happen. UniPi dead … no more lights.
    So is there another, better solution for my idea?

    As a side note, I’m looking in to http://www.openhab.org for controlling the UniPi, so if anyone knows if there is already a binding for it, that would be great !!!

    Many Thx!
    David



  • OK, I looked in to the UniPi to use it as a home automation controller for my lights in the house.
    Now I’m not sure if I can do what I’m looking for, so if anyone can help me on my way that would be great!

    At the moment my lights are switched by Hager EPN513 DIN Bistable or Latching relays (we call them Teleruptors).
    [attachment=0:enkbl4cg]Knipsel2.JPG[/attachment:enkbl4cg]

    This relays switches 240 Volts to my lamps by connecting 24 Volts buttons to it. So when I press a button on the wall it sends 24 Volts to the relay and the relays switches the 240 Volt.
    [attachment=1:enkbl4cg]Knipsel.JPG[/attachment:enkbl4cg]

    Now my question is, how can I use the unipi to switch my relays and still keep the 24 volt buttons, AND I need to know the state of the relays. Say I switch the lamp on with the UniPi and back out with the button. My software needs to know what happened there …

    I was thinking to connect my buttons to the digital inputs of the Unipi (not sure if 24 Volts is going to work) and connect my DIN relays to the relays on the UniPi. So than I can digitally turn my lights on/off with the UniPi and still use my buttons, sins they also switch the UniPi.
    Will this setup work?

    If this works there is only 1 problem … The UniPi becomes the single point of failure. Not that I don’t trust the quality of the UniPi, but things just happen. UniPi dead … no more lights.
    So is there another, better solution for my idea?

    As a side note, I’m looking in to http://www.openhab.org for controlling the UniPi, so if anyone knows if there is already a binding for it, that would be great !!!

    Many Thx!
    David



  • Hello,

    nice project! If i understand correctly, the relays switch based on one impulse, so the 24V does not have to be provided to it for the whole time it is ON, right?

    Anyway 24V is OK with the digital inputs so there is no need to worry.

    The solution you proposed will work well, but as you said, it has a single point of failure. I think (if the relays work as I described) you could lead the signal from the button to both UniPi and the relay, so your relays would work even if the UniPi is off and you would handle the signals from the button only in your software (so there is no need to do anything with relays of UniPi) but you would have to know the state of the lights when you run your software…

    But we did the same as you proposed and it works well without any problems for more than a year.

    Regarding the OpenHAB, we tried to contact them and send them a sample UniPi so they could test it but without any response... But we keep trying since the project looks promising!

    Best regards,
    Tomas



  • Hi Tomas,

    Thanks for your answer!
    You are right about the 24 Volt puls that is used to switch the relays, so NO constant 24 volt current is needed.

    I Don't fully understand your provided solution with the switching without the relays on the Unipi …
    Can you maybe make a little sketch of this setup?

    It sounds like you would connect my buttons to both the DIN relays and the inputs on the Unipi.
    So if I push a button, the light comes on (relay switches) and i get a 24 volt High input on the Unipi, so the Unipi knows the light is switched on.
    But how would I switch the lamp trough the software, there needs to go a 24 volt puls from the Unipi to the relay right?

    To bad the OpenHab people did not yet react to your offer ... it looks like a very good combination!
    Lets hope they come around ...

    GreetZ,
    David



  • Hello David,

    you are correct. That's what I meant. Plus, as you said, you would need the 24V to go from the power supply to the relays of UniPi and to the button so you could switch the Teleruptors (which switch on the light) by the UniPi and by the button.

    Simple wiring diagram:
    24V -> Button -> UniPi Digital Input + Teleruptor –> so the light switches every time you press the button plus UniPi knows that you switched it manually
    24V -> UniPi Relay -> Teleruptors

    [attachment=0:1btsrd7c]20150209_120857_.jpg[/attachment:1btsrd7c]

    But you would have to deal with the digital input event after you turn on the relay on UniPi.

    Hope it helps.

    Best regards,
    Tomas