dbus-mqtt-battery - Emulates a physical battery from MQTT data

GitHub repository: mr-manuel/venus-os_dbus-mqtt-battery

Disclaimer

I wrote this script for myself. I'm not responsible, if you damage something using my script.

Purpose

The script emulates a battery in Venus OS. It gets the MQTT data from a subscribed topic and publishes the information on the dbus as the service com.victronenergy.battery.mqtt_battery with the VRM instance 41.

Config

Copy or rename the config.sample.ini to config.ini in the dbus-mqtt-battery folder and change it as you need it.

JSON structure

Required data

{
    "dc": {
        "power": 79.6,
        "voltage": 58.1,
        "current": 1.4,
        "temperature": 23
    },
    "consumed_amphours": 2.9,
    "soc": 99,
    "history": {
        "voltageMin": 0,
        "voltageMax": 0
    }
}

Install

1. Copy the dbus-mqtt-battery folder to /data/etc on your Venus OS device

2. Run bash /data/etc/dbus-mqtt-battery/install.sh as root

   The daemon-tools should start this service automatically within seconds.

Uninstall

Run /data/etc/dbus-mqtt-battery/uninstall.sh

Restart

Run /data/etc/dbus-mqtt-battery/restart.sh

Debugging

The logs can be checked with tail -n 100 -f /data/log/dbus-mqtt-battery/current | tai64nlocal

The service status can be checked with svstat svstat /service/dbus-mqtt-battery

This will output somethink like /service/dbus-mqtt-battery: up (pid 5845) 185 seconds

If the seconds are under 5 then the service crashes and gets restarted all the time. If you do not see anything in the logs you can increase the log level in /data/etc/dbus-mqtt-battery/dbus-mqtt-battery.py by changing level=logging.WARNING to level=logging.INFO or level=logging.DEBUG

If the script stops with the message dbus.exceptions.NameExistsException: Bus name already exists: com.victronenergy.battery.mqtt_battery" it means that the service is still running or another service is using that bus name.

Compatibility

It was tested on following devices:

• RaspberryPi 4b
• MultiPlus II (GX Version)

Screenshots

MQTT Battery