M-bus meter to UniPi?



  • Hej team,

    For our prototype setup, we need to read the status of 3 energy meters. 2 of them are communicating on m-bus, and the 3rd is communicating on RS485.

    Can someone help me on how to connect the hardware to the UniPi?

    • how to wire m-bus connectors (2 wires)?
    • how to wire RS485?

    I have some M-bus to TTL converters based on TI TSS721A M-bus transciever.

    http://www.ti.com/product/TSS721A

    Looking forward to hearing from you

    best regards from Morten in Denmark



  • Hej team,

    For our prototype setup, we need to read the status of 3 energy meters. 2 of them are communicating on m-bus, and the 3rd is communicating on RS485.

    Can someone help me on how to connect the hardware to the UniPi?

    • how to wire m-bus connectors (2 wires)?
    • how to wire RS485?

    I have some M-bus to TTL converters based on TI TSS721A M-bus transciever.

    http://www.ti.com/product/TSS721A

    Looking forward to hearing from you

    best regards from Morten in Denmark



  • RS 485 can be easily done with USB->RS485 converter (also available in our shop)
    However the m-bus is not that easy because the mbus master acts as a power supply for the meters to communicate, however there are mbus masters which you can interface using RS232



  • Hej Tomas,

    Thank you for your reply.

    If I have this module:
    http://www.cdiscount.com/informatique/c ... 55531.html

    Would it not be possible for me to connect via UART, like described in this post:
    http://electronics.stackexchange.com/qu ... rduino-rpi

    How should I make MERVIS discover the MBUS connection on the UART?

    rgs Morten:)



  • I cannot confirm that your HW will work but in mervis, you can just create a new channel with Mbus protocol, configure it and then you should be good to go with detection of the sensors.

    Actually I have not tried that because I do not have a mbus meter, so it would be great to share your experience.