Smartmeter Landis+Gyr E450: SML format in Switzerland (EWB)

[TheNetStriker]

I just got my new Landis+Gyr E450 Smartmeter in Switzerland (EWB) and I tried to get the data from it using various posts I found here. But none of the SML messages I found seem to match the format my Smartmeter sends. So I invested some time to analyze the SML message.

What I found out so far is that this smartmeter first sends a header with all the OBIS codes that are transmitted. The data from the codes is transmitted after the header.

Here is an examle of the data and what I found out so far. (I obfuscated the smartmeter ID)

02 05 01 05 02 04 12 00 28 09 06 00 08 19 09 00 ff 0f  header 0-8 25.9.0
02 12 00 00 02 04 12 00 28 09 06 00 08 19 09 00 ff 0f  header 0-8 25.9.0
01 12 00 00 02 04 12 00 01 09 06 00 00 60 01 01 ff 0f  header 0-0 96.1.1
02 12 00 00 02 04 12 00 03 09 06 01 00 01 07 00 ff 0f  header 1-0 1.7.0
02 12 00 00 02 04 12 00 03 09 06 01 00 02 07 00 ff 0f  header 1-0 2.7.0
02 12 00 00 09 06 00 08 19 09 00 ff                               header 0-8 25.9.0
09                                                                                    Begin of data?
06                                                                                    Start of value
31 32 33 34 35 36                                                           Smartmeter id
06                                                                                    Start of value
00 00 01 b3                                                                     OBIS 1.7.0 data
06                                                                                    Start of value
00 00 00 00                                                                     OBIS 2.7.0 data
00 01 b3 06 00 00 00 00                                                 Same data again?

At the moment the only way to read this data is by extracting the raw bytes with offsets. But this would cause problems if they change what is transmitted in each packet after some time

Does anyone know what kind of SML standard this is? And could this standard be implemented in Tasmota?

[TheNetStriker]

I think I figured out how the communication works now and was able to decode all data using the Gurux GLDLSMDirector.

The Landis+Gyr E450 sends HDLC packets containing DLMS data as HDLC BlockData. The data is sent in multiple HDLC packets and the DLMS data has to be combined to make sense. After the block data is combined I was able to convert the DLMS data to XML using GLDLSMDirector.

This is what I get from one DLMS message in GLDLSMDirector. (I obfuscated the smart meter Id)

<DataNotification>
  <!-- Invoke ID: 232499 -->
  <LongInvokeIdAndPriority Value="00038C33" />
  <!-- 28.04.2025 18:56:10 -->
  <DateTime Value="07E9041C0112380AFF800000" />
  <NotificationBody>
    <DataValue>
      <Structure Qty="05" >
        <Array Qty="05" >
          <Structure Qty="04" >
            <UInt16 Value="0028" />
            <!-- 0.8.25.9.0.255 -->
            <OctetString Value="0008190900FF" />
            <Int8 Value="02" />
            <UInt16 Value="0000" />
          </Structure>
          <Structure Qty="04" >
            <UInt16 Value="0028" />
            <!-- 0.8.25.9.0.255 -->
            <OctetString Value="0008190900FF" />
            <Int8 Value="01" />
            <UInt16 Value="0000" />
          </Structure>
          <Structure Qty="04" >
            <UInt16 Value="0001" />
            <!-- 0.0.96.1.1.255 -->
            <OctetString Value="0000600101FF" />
            <Int8 Value="02" />
            <UInt16 Value="0000" />
          </Structure>
          <Structure Qty="04" >
            <UInt16 Value="0003" />
            <!-- 1.0.1.7.0.255 -->
            <OctetString Value="0100010700FF" />
            <Int8 Value="02" />
            <UInt16 Value="0000" />
          </Structure>
          <Structure Qty="04" >
            <UInt16 Value="0003" />
            <!-- 1.0.2.7.0.255 -->
            <OctetString Value="0100020700FF" />
            <Int8 Value="02" />
            <UInt16 Value="0000" />
          </Structure>
        </Array>
        <!-- 0.8.25.9.0.255 -->
        <OctetString Value="0008190900FF" />
        <!-- 123456 -->
        <OctetString Value="313233343536" />
        <UInt32 Value="000001B3" />
        <UInt32 Value="00000000" />
      </Structure>
    </DataValue>
  </NotificationBody>
</DataNotification>

I suspect the problem that Tasmota cannot identify the data by OBIS code could be that this smart meter first sends all the OBIS codes as an array and only after that it sends all the data values.

So far I found one Python project that puts those OBIS codes and the data back together. Here is a Link to the code:
https://github.com/scs/smartmeter-datacollector/blob/master/smartmeter_datacollector/smartmeter/hdlc_dlms_parser.py

@gemu2015 Could you maybe take a look at this? Would it be possible to handle this data structure in Tasmota? It would be much nicer to just configure the OBIS codes instead of working with byte offsets.

[gemu2015]

i am in vacation and after blocked for some more weeks.
i may have a look in summer but i would need at least one valid data block for testing

[TheNetStriker]

@gemu2015 No problem, take your time. I can work with the offsets until then.

Here are two HDLC messages from the device that result in one DLMS message:
7E A0 84 CE FF 03 13 12 8B E6 E7 00 E0 40 00 01 00 00 70 0F 00 03 8C 33 0C 07 E9 04 1C 01 12 38 0A FF 80 00 00 02 05 01 05 02 04 12 00 28 09 06 00 08 19 09 00 FF 0F 02 12 00 00 02 04 12 00 28 09 06 00 08 19 09 00 FF 0F 01 12 00 00 02 04 12 00 01 09 06 00 00 60 01 01 FF 0F 02 12 00 00 02 04 12 00 03 09 06 01 00 01 07 00 FF 0F 02 12 00 00 02 04 12 00 03 09 06 01 00 02 07 00 FF 0F 02 12 00 00 E6 9A 7E

7E A0 2B CE FF 03 13 2A 0B E0 C0 00 02 00 00 1A 09 06 00 08 19 09 00 FF 09 06 36 31 35 38 33 39 06 00 00 01 B3 06 00 00 00 00 6D 35 7E

And here is the DLMS message data of those two HDLC messages:
0F 00 03 8C 33 0C 07 E9 04 1C 01 12 38 0A FF 80 00 00 02 05 01 05 02 04 12 00 28 09 06 00 08 19 09 00 FF 0F 02 12 00 00 02 04 12 00 28 09 06 00 08 19 09 00 FF 0F 01 12 00 00 02 04 12 00 01 09 06 00 00 60 01 01 FF 0F 02 12 00 00 02 04 12 00 03 09 06 01 00 01 07 00 FF 0F 02 12 00 00 02 04 12 00 03 09 06 01 00 02 07 00 FF 0F 02 12 00 00 09 06 00 08 19 09 00 FF 09 06 36 31 35 38 33 39 06 00 00 01 B3 06 00 00 00 00

Have a great vacation.