IEC 62056-21 Energy meter

  • Hello,
    I'm planning to build a MySensor node to read my energy meter using the optic interface.
    That interface communicates through the protocol IEC62056-21 / IEC1107

    Anyone have already used this procotol?

  • Hero Member

    @diogoc Not familiar with that protocol, but it would be quite easy to read UART through an optical isolator, if you were to decide on that instead.

  • I have almost working this communication.

    Comercial optical probes like this are expensive:
    Optical probe

    So I build a optical probe based on this schematic
    DIY 62056-21 optical probe

    Communication protocol tested on my meter:

    Baudrate: 300 bps, 7 bits, parity even, 1 stop bit
    Send:     /?!<CR><LF>         (wake-up and sign-on)
    Receive:  /XXX5YYYYY<CR><LF>  (XXX is the manufacturer ID; YYYYY is the meter ID; 5 is the new baudrate = 9600 bps)
    Send:     <ACK>050<CR><LF>    (send ack; reading mode)
    Baudrate: 9600 bps, 7 bits, parity even, 1 stop bit
    Received: C.1(201236731.0(01:39 25-08-18)

    Now I only have to parse the values of tarif 1 (1.8.1), tarif 3 (1.8.3), and total (1.8)

  • @diogoc Did you make it work eventually?
    What code did you use?
    Did you build optical probe only by the left part of the diagram, ignoring USB interface?
    I found someone selling DIY kit as per diagram above

  • This looks like the DSMR meters, you can read it without optical isolation as the meter itself is already isolated.
    Google on DSMR reading and you will find lots of examples

  • Yes I have it working.
    Just send the commands "/?!<CR><LF>" and "<ACK>050<CR><LF>" and read the response back.
    I used the left part of schematic and connected the RX and TX directly to the atmega328.

    @electrik my meter don't have a physical communication port, so I have to use the optic interface

  • @diogoc do you have a working sketch? I worked on the same topic for a landys & gyr uh50 heat counter. It's not a real 62056-21 protocol, initialization is different.
    Best regards