P1 meter script

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I was not happy with the Marstek CT003 that was included with my Marstek Venus e battery because of an unstable wifi connection and decided to use my existing P1 reader combined with the b2500-meter script to get a reliable CT connection.

In many countries smart meters with a so-called p1 port (according to the (D/E)SMR 2/4/5 standard) are deployed (Netherlands, Belgium, Luxemburg, Austria, Sweden, Denmark) so I guess my efforts might be useful to others as well.

Because I have a ' rock-steady' P1 reader that consists of a P1 USB cable + a ser2net process that publishes every P1 telegram on a configurable tcp port, I created a small pyhton script that extracts the active power readings (both 1phase and 3phase supported) from the P1 telegram and provides it to the B2500-meter script.
I have configured the b2500-meter scipt to emulate a shellypro3em and my Marstek Venus e is configured to use the shellypro3em as CT sensor.

Note:

• The DSMR4 and below versions of these smart meters deliver one P1 telegram every 10 seconds which makes the charge-discharge behaviour of your Marstek battery laggy
• The (E)SMR5 version of these smart meters deliver one P1 telegram every second which appears to work pretty well to make the Marstek battery charge/discharge with (almost) no injection to the grid.

HowTo:
First of all make sure to follow the b2500-meter install instructions (I used the stand-alone setup because I do not use Docker or Home Assistant). Then:

1. Make sure you have your P1 USB cable up and running
2. Have ser2net setup and running using a /etc/ser2net.yaml that contains something similar to (the P1 USB cable connected to /dev/ttyUSBP1):

connection: &p1
    accepter: tcp,3000
    enable: on
    options:
      max-connections: 4
    connector: serialdev,
              /dev/ttyUSBP1,
              115200n81,local

3. Copy attached p1net.py and p1net.sh scripts in the folder that contains the b2500-meter project (in my case the folder is named "/home/dietpi/marstek-P1meter/"). Make sure to edit ip and port in the p1net.sh script so it matches the ser2net.yaml contents!
4. In the b2500-meter config.ini include the following:

[GENERAL]
DEVICE_TYPE = shellypro3em

and

[SCRIPT]
COMMAND = /home/dietpi/marstek-P1meter/p1net.sh

The most convenient way to run everything is by creating service files and run both ser2net and the b2500-meter script as a daemon.

p1net.zip