Victron dbus MQTT Mapper

This mapper takes a json message from the source MQTT broker and reformats the values to be published to Victron VenusOS device.

On the Venus device this message gets converted to a device using the dbus-mqtt-services script.

Usage

The script can be executed using Python and Docker.

Before you start, edit the ip addresses of the MQTT server and your Victron device and the source message topic in the file header.

Start script using Python

1. Start the script using python3 dbus_mapper.py

Start script using Docker

1. Ensure you have Docker installed: https://docs.docker.com/get-docker/
2. Build container using docker build -t victron-mqtt-mapper .
3. Start container using docker run --name victron-mqtt-mapper -d victron-mqtt-mapper

Mapping

Mapping is done using the mapper.json file.

mapper.json header

This file has the header in the device section:

{
    "device": {
        "service": "p1_grid_1",
        "serviceType": "grid",
        "serviceInstance": 0,
        "dbus_data": [
            {
                "path": "/Mgmt/ProcessName",
                "value": "P1 Bridge",
                "valueType": "string",
                "writeable": false
            },
            {
                "path": "/Mgmt/ProcessVersion",
                "value": "1.0",
                "valueType": "string",
                "writeable": false
            },
            {
                "path": "/Mgmt/Connection",
                "value": "MQTT P1",
                "valueType": "string",
                "writeable": false
            },
            {
                "path": "/ProductId",
                "value": "45069",
                "valueType": "integer",
                "writeable": false
            },
            {
                "path": "/ProductName",
                "value": "P1 Energy Meter",
                "valueType": "string",
                "writeable": false
            },
            {
                "path": "/FirmwareVersion",
                "value": "1.0",
                "valueType": "string",
                "writeable": false
            },
            {
                "path": "/HardwareVersion",
                "value": "1.0",
                "valueType": "string",
                "writeable": false
            },
            {
                "path": "/CustomName",
                "value": "P1 MQTT Mapper",
                "valueType": "string",
                "writeable": true
            }

mapper.json mapping fields

The fields to be mapped from the source message are in the dbus_fields section. This way, MQTT data from existing devices can easily be mapped to a Victron device.

• name : field in the source
• path : the path on the dbus the value is posted to
• valueTtype : the valueType used
• unit: optional unit displayed on the Victron UI
• multiplier: optional multiplier for the value (e.g. 0.001 to divide by 1000 to go from W to kW) (note: the description is not relevant for the working)

    },
    "dbus_fields": [
        {
            "name": "PowerSumActual",
            "unit": "W",
            "valueType": "float",
            "description": "Actual electricity power imported - power exported in 1 Watt resolution",
            "path": "/Ac/Power"
        },
        {
            "name": "electricityImportedToday",
            "unit": "kWh",
            "valueType": "float",
            "description": "Actual electricity power delivered (+P) in 1 Watt resolution",
            "path": "/Ac/Energy/Forward",
            "multiplier": 0.001,
            "digits": 3
        },
    ]}

Screenshot of result