Remembering template sensor state after reboot

Configuration
1

Hey,

so I would like to track the odometer reading of my EV since last charge. I’ve created a template sensor:

  template:
    - trigger:
        - platform: state
          entity_id:
            - sensor.citroen_ec4_charging_mode
          from:
            - Quick
            - Slow
          to: No
      sensor:
        - name: "Citroen EC4 Last Charge Finished Mileage"
          state: "{{ states('sensor.citroen_ec4_mileage') }}"
        - name: "Citroen EC4 Last Charge Finished Battery Level"
          state: "{{ states('sensor.citroen_ec4_battery_level') }}"

But afaik it looses value if I restart hass. And that if I understand correctly is expected. Any work around to this?

Another way would be to probably use automation + input_number sensor, and then as automation action use a input_number.set_value service. This way the input number would be persisted across hass reboots?

3

Can you give more details on this one? Or do you mean that adding event_type: event_template_reloaded is enough?

4

Yes. Simply using the code posted is enough. Notice @123 has also included if statements in the sensor templates.

6

Thanks, I was just under impression that I also need to do something not just copy paste :slight_smile:

Anyhow, it does seem that home assistant restarting is not the only issue. Though the sensor.citroen_ec4_charging_mode changed couple of times today, this template stayed in the “unknown” state, so will have to see what is up with that

7

Check the developer tools state tab - there is a very good chance that the states are actually lowercase - eg:
“quick” “slow” “no”

8

I deleted my original post because, based on the documentation and tests I have performed, a Trigger-based Template Sensor’s state is restored after a restart.

From Trigger-Based Template Sensor documentation:

The state, including attributes, of trigger-based sensors and binary sensors is restored when Home Assistant is restarted.

Your two Trigger-based Template Sensors simply report the value of two Citroen-based sensors. You should confirm that those two Citroen sensors (mileage/battery_level) report proper values at all times, even after startup.

If your two Trigger-based Template Sensors fail to update at all times then there’s a problem with the State Trigger (follow the advice from mobile.andrew.jones regarding the spelling of the state values).

9

well this is totally weird. The values are uppercase, no issue here.

Screenshot 2022-09-02 at 20.07.24
Screenshot 2022-09-02 at 20.07.242072×544 56.9 KB

I’ve plugged/unplugged the car three times yesterday, and the template sensor stayed in the unknown state.

Tried changing from to not_from, no luck either

          not_from:
            - "unknown"
            - "unavailable"
          to: "No"

Then I decided to add an automation with input number instead.

  automation:
    - alias: Set After charge mileage
      trigger:
        - platform: state
          entity_id:
            - sensor.citroen_ec4_charging_mode
          not_from:
            - "unknown"
            - "unavailable"
          to: "No"
      action:
        service: input_number.set_value
        data:
          entity_id: input_number.citroen_ec4_last_charge_finished_mileage_test
          value: "{{ states('sensor.citroen_ec4_mileage') }}"
  input_number:
    citroen_ec4_last_charge_finished_mileage_test:
      name: Citroen EC4 Last Charge Finished Mileage
      min: 0
      max: 999999
      unit_of_measurement: km

plugged/unplugged, and bam - automation with input_number seemed to work. Thinking that I’m just gonna stick to that went to delete the template sensor, and surprise surprise - that one also had a value!

So probably gonna leave those two for a while to see if they always work :confused:

Thanks you all for help

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