Sensor Integration Home Assistant

The Senvolon level sensor is integrated into Home Assistant via MQTT. From firmware version 3.8, the sensor supports MQTT Discovery, which allows Home Assistant to automatically detect and integrate the sensor values. Manual configuration is still possible. This guide shows all the steps you need to take in Home Assistant to receive and display sensor readings.

Why use MQTT for the level sensor

• Reliable communication between sensor and Home Assistant
• Automatic detection by MQTT Discovery
• Fast update of measurement values
• Flexible expandability for additional sensors

Prerequisites for integration

• Senvolon level sensor from version 3.8
• Home Assistant
• MQTT broker like Mosquitto
• Correctly set MQTT topic in the sensor

1. Install MQTT broker in Home Assistant

If no MQTT broker is yet available:

1. Open Settings → Add-ons
2. Go to the Add-on Store
3. Install the Mosquitto MQTT Broker

2. Activate and configure MQTT in Home Assistant

1. Go to Settings → Devices & Services
2. Add the MQTT service
3. Complete the configuration

Note: If Mosquitto was installed as an add-on, the broker automatically uses the Home Assistant IP address. Username and password correspond to your Home Assistant credentials.

3. Supplement configuration.yaml

To ensure Home Assistant correctly reads all sensor values, the central configuration file needs to be extended.

Install File Editor

1. Open Settings → Add-ons → Add-on Store
2. Install the File Editor
3. Activate its display in the sidebar
4. Open the configuration.yaml file

Enter MQTT sensors

Replace TOPIC with the MQTT topic you set in the level sensor.

mqtt:
  sensor:
    - name: "Level"
      unique_id: "LS_Level"
      state_topic: "stat/TOPIC/REL_LEVEL"
      unit_of_measurement: "%"
      icon: mdi:car-coolant-level
      device:
        identifiers: "LevelSensor"
        manufacturer: "Senvolon"
        name: "Level Sensor"
        model: "V1"

    - name: "Fluid"
      unique_id: "LS_Fluid"
      state_topic: "stat/TOPIC/FILLING"
      unit_of_measurement: "l"
      icon: mdi:water
      device:
        identifiers: "LevelSensor"
        manufacturer: "Senvolon"
        name: "Level Sensor"
        model: "V1"

    - name: "Distance"
      unique_id: "LS_Distance"
      state_topic: "stat/TOPIC/DISTANCE"
      unit_of_measurement: "cm"
      icon: mdi:waves-arrow-up
      device:
        identifiers: "LevelSensor"
        manufacturer: "Senvolon"
        name: "Level Sensor"
        model: "V1"

    - name: "Height"
      unique_id: "LS_Height"
      state_topic: "stat/TOPIC/LEVEL"
      unit_of_measurement: "cm"
      icon: mdi:waves
      device:
        identifiers: "LevelSensor"
        manufacturer: "Senvolon"
        name: "Level Sensor"
        model: "V1"

    - name: "Alert"
      unique_id: "LS_Alert"
      state_topic: "stat/TOPIC/ALERT"
      icon: mdi:alert-circle-outline
      device:
        identifiers: "LevelSensor"
        manufacturer: "Senvolon"
        name: "Level Sensor"
        model: "V1"

Check syntax and save

• Red exclamation mark = error
• Green check mark = syntax correct
• Then save the file

4. Restart Home Assistant

Reload once via Developer Tools → Restart.

5. See the level sensor in Home Assistant

After the restart, Home Assistant automatically detects the sensor. The values are updated as soon as new data arrives from the sensor.