Notify when no update in some amount of time

[sd_dracula]

I need to create an automation which notifies me when a sensor has not been updated in X amount of minutes but not sure how to formulate the automation, i.e. what trigger to use
I assume it is the state trigger but how to set it up?

[zoogara (Daryl)]

If your sensor times out and goes unavailable, you can use something like this:

- alias: lux_out_of_service
  initial_state: true
  trigger:
    platform: state
    entity_id: sensor.front_verandah_lux
    to: unavailable
    for: 00:45:00
  action:
    service: persistent_notification.create
    data_template:
      message: Front verandah lux sensor battery flat?

Te lux sensor has an expire_after value to make it go unavailable:

  - platform: mqtt
    name: "Front Verandah Lux"
    state_topic: "lux_sensor/sensor/bh1750_illuminance/state"
    device_class: illuminance
    unit_of_measurement: "lx"
    expire_after: 900

[zoogara (Daryl)]

BTW if it’s not a MQTT sensor, or doesn’t go unavailable when not updated - you can do a trigger when the state doesn’t change in x amount of time:

  trigger:
    - platform: state
      entity_id: sensor.front_verandah_lux
      for: "00:45:00"

[vingerha]

Yoo can use a template for e.g. last_updated or last_changed, depends on what you are looking for

{{ ((as_timestamp(now()) - as_timestamp(states.YOURSENSOR.last_changed))  / 60) |  int  }}

[sd_dracula]

Yes I think this is the one as it’s value remains the same and won’t go to unavailable

[vingerha]

Depends if it is just the state that you are looking at

[sd_dracula]

I tried the template but it doesn’t work for me as the value for {{states.solar_battery_power.last_changed}} is equal to None when it obviously should be 4 mins:

[vingerha]

pols click on the sensor and show me the info that then shows on the top

[vingerha]

@sd_dracula

{{states.solar_battery_power.last_changed}}

It should be

{{ states.sensor.solar_battery_power.last_changed }}

[sd_dracula]

Yes that was it, missing the sensor part
Thanks

[123 (Taras)]

@sd_dracula

me when a sensor has not been updated in X amount of minutes

Basically, you want a “stale sensor” detector. I provided an example here:

Notification in case no values have been recorded since X

One way to detect if a sensor’s value is stale (i.e. has not changed for a long time) is to compare the entity’s last_changed to the current time. If it’s more than some threshold value, like 30 minutes, that means the entity’s value hasn’t changed in the past half-hour. You can create an automation with a Template Trigger that triggers when the monitored temperature sensor is stale. The action can be whatever you want. It can log the incident to a file, notify you, do both and more. In the exa…