Lamp that was last turned off or on

Configuration
1

Hello everyone,

I would like to make a sensor that keeps track of which lamp was last turned on and off.
I’ve tried everything, but it won’t work.
Can anyone help me with this?
Thanks for every response.

2

Can you clarify what you want? Does current state matter?

For example:

If lights turn on in order A, B, C then turn off in order C, A… should the sensor return C because it was the last turned on or B because it was the last turned on that is still on?

The following will give you the last light that was turned on, that is still on:

template:
  - sensor:
    - name: "Last Light On"
      unique_id: last_light_on_001
      state: |
        {{ states.light | selectattr('state', 'eq', 'on') | sort(attribute = 'last_changed', reverse=1 ) 
        | map(attribute='entity_id') | first }}
      attributes:
        count: "{{states.light | selectattr('state', 'eq', 'on') | list | count}}"
      availability: |-
        {{states.light | selectattr('state', 'eq', 'on') | list | count > 0 }}
    - name: "Last Light Off"
      unique_id: last_light_off_001
      state: |
        {{ states.light | selectattr('state', 'eq', 'off') | sort(attribute = 'last_changed', reverse=1 ) 
        | map(attribute='entity_id') | first }}
      attributes:
        count: "{{states.light | selectattr('state', 'eq', 'off') | list | count}}"
      availability: |-
        {{states.light | selectattr('state', 'eq', 'off') | list | count > 0 }}

If you are interested in the most recent light that was turned on, no matter its current state, you will need the above and the following:

  - trigger:
      - platform: state
        entity_id: sensor.last_light_on
        not_to:
          - unknown
          - unavailable
        not_from:
          - unknown
          - unavailable
    sensor:
      - name: "Most Recently Turned On Light"
        unique_id: most_recent_turned_on_001
        state: |
          {% set current = this.state %}
          {% set new = trigger.to_state.attributes.count > trigger.from_state.attributes.count %}
          {{ trigger.to_state.state if new else current }}  
  - trigger:
      - platform: state
        entity_id: sensor.last_light_off
        not_to:
          - unknown
          - unavailable
        not_from:
          - unknown
          - unavailable
    sensor:
      - name: "Most Recently Turned Off Light"
        unique_id: most_recent_turned_off_001
        state: |
          {% set current = this.state %}
          {% set new = trigger.to_state.attributes.count > trigger.from_state.attributes.count %}
          {{ trigger.to_state.state if new else current }}

FWIW, there are a lot of light entities that you might not consider useful for your purposes like indicator leds or displays. In that case you might want to consider setting up a group for just lights that you actually want to track.

1 Like
3

Any light turned off last should be in turned on state, no?

4

At this point I would say that any light turned off last should be either off or on… :upside_down_face:

5

How can I use this with a group of lights?

6

Basically, replace

states.light | selectattr('state', 'eq', 'on')

with

state_attr('light.YOUR_LIGHT_GROUP', 'entity_id') | select('is_state','on')| expand

1 Like
7

This is awesome! works perfectly.

is it possible to add a brightness attribute?
i tried it, but i cannot make it work.

i tried this before giving up:

brightness: “{{ state_attr(‘light.YOUR_LIGHT_GROUP’, ‘entity_id’) | select(‘is_state’,‘on’)| expand | sort(attribute = ‘last_changed’, reverse=1 ) | map(attribute=‘brightness’) | first }}”

But the brightness attribute shows no status.

8

You’re 95% there… You just need to adjust map to go into the attributes of the state object:

{{ state_attr('light.YOUR_LIGHT_GROUP', 'entity_id') 
| select('is_state','on') | expand 
| sort(attribute = 'last_changed', reverse=1 ) 
| map(attribute='attributes.brightness') | first | default(0, true) }}

One thing to note is that this will return a brightness, if you want a percentage you’ll need to divide the output by 2.55.

Brightness Percentage example 
{{ (state_attr('light.YOUR_LIGHT_GROUP', 'entity_id') 
| select('is_state','on') | expand 
| sort(attribute = 'last_changed', reverse=1 ) 
| map(attribute='attributes.brightness') | first 
| default(0, true) / 2.55) | int }}
1 Like