Home Assistant: motion sensor coupled with a switch

Have you ever waved your arms at a motion sensor to turn on your outdoor light while having dinner on the deck? It happened to me all the time and was really frustrating… so I created an automation to stop it! 😎

What do you need?

• A smart bulb (or equivalent to control a bulb)

• A smart motion sensor

• A input_boolean to check the way the light is powered on

Input Boolean

#

Nothing special here, you just need to put it within your input_boolean.yaml file or directly in the configuration.yaml, depending on how you are managing your HassIO configuration.
To simplify things, I put this in my global configuration file: input_boolean: !include components/input_boolean.yaml

input_boolean: !include components/input_boolean.yaml

This lets you keep all boolean configurations in one file.

Another approach, which I use for automations, is to use a folder and let Home Assistant merge everything: automation: !include_dir_merge_list automations/

automation: !include_dir_merge_list automations/

This lets you put one YAML per automation, keeping things organized.

Back to our boolean. What to put in the file:

terrasse_salon_auto_on:
  name: Terrasse Salon Motion ON
  icon: mdi:lightbulb

This will create an input_boolean named terrasse_salon_auto_on we will use later in our automation.

The Automation

#

We have two automations: one for power-on, one for power-off.

- alias: Terrasse Salon ON
  id: terrasse_salon_on
  trigger:
    platform: state
    entity_id: binary_sensor.motion_salon_occupancy
    to: "on"
  condition:
    - condition: state
      entity_id: light.terrasse_salon
      state: "off"
    - condition: numeric_state
      entity_id: sensor.motion_salon_illuminance_lux
      below: 50
    - condition: state
      entity_id: input_boolean.terrasse_motion_sensor_enabled
      state: "on"
  action:
    - service: light.turn_on
      entity_id: light.terrasse_salon
    - service: input_boolean.turn_on
      entity_id: input_boolean.terrasse_salon_auto_on

- alias: Terrasse Salon OFF
  id: terrasse_salon_off
  trigger:
    platform: state
    entity_id: binary_sensor.motion_salon_occupancy
    to: "off"
    for:
      minutes: 2
  condition:
    - condition: state
      entity_id: light.terrasse_salon
      state: "on"
    - condition: or
      conditions:
        - condition: state
          entity_id: input_boolean.terrasse_salon_auto_on
          state: "on"
        - condition: state
          entity_id: input_boolean.ignore_light_manual_on
          state: "on"
  action:
    - service: light.turn_off
      entity_id: light.terrasse_salon
    - service: input_boolean.turn_off
      entity_id: input_boolean.terrasse_salon_auto_on

Let’s go through each part to understand how it works.

The Trigger

#

We want to control the light based on motion detection, so we use a state trigger on the motion sensor.

trigger:
    platform: state
    entity_id: binary_sensor.motion_salon_occupancy
    to: "on"

When the occupancy sensor turns on, the automation triggers.

For the off trigger, we improve it slightly to prevent flickering when movement isn’t constant.

trigger:
    platform: state
    entity_id: binary_sensor.motion_salon_occupancy
    to: "off"
    for:
      minutes: 2

The for: minutes handles this: if occupancy is off for 2 minutes, the action triggers.

The Conditions

#

When there’s motion, when should the light turn on? When it’s dark and the light is off, of course.

condition:
    - condition: state
      entity_id: light.terrasse_salon
      state: "off"
    - condition: numeric_state
      entity_id: sensor.motion_salon_illuminance_lux
      below: 50
    - condition: state
      entity_id: input_boolean.terrasse_motion_sensor_enabled
      state: "on"

• The state part is checking if the light is off

• numeric_state checks the motion sensor’s illuminance value. What value to use? I ran some tests. 0 would work (no light), but I moved it up slightly to also trigger in low light.

• The last state is another input_boolean that can completely disable the light. I use this at night: if the alarm is on, no one will be outside, so motion shouldn’t turn on the light.

The power-off automation is similar, but this is where the magic happens with our input_boolean.

  condition:
    - condition: state
      entity_id: light.terrasse_salon
      state: "on"
    - condition: or
      conditions:
        - condition: state
          entity_id: input_boolean.terrasse_salon_auto_on
          state: "on"
        - condition: state
          entity_id: input_boolean.ignore_light_manual_on
          state: "on"

• The light must be on.

• The input_boolean we configured. The light turns off only if it was turned on by automation. If we turned it on manually, the flag stays false and the light won’t turn off automatically.

• There’s also an or condition with a second boolean that overrides this: it forces the light off regardless of how it was turned on.

The Action

#

If conditions are met, the light turns on or off — and we also control the input_boolean.

  action:
    - service: light.turn_on
      entity_id: light.terrasse_salon
    - service: input_boolean.turn_on
      entity_id: input_boolean.terrasse_salon_auto_on

The turn-on script fires two services: one for the light, one to set the boolean to true. This marks that the light was turned on by automation.
This is the simplest way I’ve found, but there are other approaches.

The power-off does the opposite: it sets the flag back to false.

  action:
    - service: light.turn_off
      entity_id: light.terrasse_salon
    - service: input_boolean.turn_off
      entity_id: input_boolean.terrasse_salon_auto_on