KNX - relative dimming for lights blueprint

knx-relative-dimming-for-lights.yaml

blueprint:
  name: KNX - relative dimming for lights
  description: Control Home Assistant light entities from KNX switching and relative dimming (DPT 3.007) telegrams.
  homeassistant:
    # `knx.telegram` trigger and `enabled` templates require Home Assistant 2024.6.0
    min_version: "2024.6.0"
  domain: automation
  input:
    target_lights:
      name: Light
      description: The lights that shall be controled.
      selector:
        target:
          entity:
            domain: light
    switch_address:
      name: Switch group address
      description: >
        Group address for switching the lights on and off. DPT 1
        Example: '1/2/3'
      default: null
    dimm_address:
      name: Relative dimming address
      description: >
        Group address for dimming the lights. DPT 3.007
        Example: '1/2/4'
      default: null
    dimm_time:
      name: Dimm time
      description: Time dimming from 0 to 100% shall take.
      selector:
        number:
          min: 1
          max: 20
          step: 0.1
          unit_of_measurement: seconds
          mode: slider
      default: 4
    dimm_steps:
      name: Dimm steps
      description: Steps used to dimm from 0 to 100%.
      selector:
        number:
          min: 2
          max: 100
          step: 1
          unit_of_measurement: steps
          mode: slider
      default: 20

# no matched condition stops repeat sequence to stop dimming (dimm 0)
mode: restart
max_exceeded: silent

variables:
  _dimm_time: !input dimm_time
  _dimm_steps: !input dimm_steps
  dimm_time: "{{ _dimm_time|float }}"
  dimm_steps: "{{ _dimm_steps|int }}"
  dimm_step: "{{ (255 / dimm_steps) | round(0, 'ceil') }}"
  dimm_delay: "{{ dimm_time * 1000 / dimm_steps }}"

trigger_variables:
  _switch_address: !input switch_address
  _dimm_address: !input dimm_address

trigger:
  - platform: knx.telegram
    destination: !input switch_address
    group_value_read: false
    group_value_response: false
    id: "switch"
    enabled: "{{ _switch_address != None }}"
  - platform: knx.telegram
    destination: !input dimm_address
    group_value_read: false
    group_value_response: false
    id: "dimm"
    enabled: "{{ _dimm_address != None }}"

action:
  - choose:
    # TURN ON
    - conditions:
        condition: and
        conditions:
          - condition: trigger
            id: "switch"
          - "{{ trigger.payload == 1 }}"
      sequence:
        - service: light.turn_on
          target: !input target_lights
    # TURN OFF
    - conditions:
        condition: and
        conditions:
          - condition: trigger
            id: "switch"
          - "{{ trigger.payload == 0 }}"
      sequence:
        - service: light.turn_off
          target: !input target_lights
    # DIMM UP
    - conditions:
        condition: and
        conditions:
          - condition: trigger
            id: "dimm"
          - "{{ 9 <= trigger.payload <= 15 }}"
      sequence:
        - repeat:
            count: '{{ dimm_steps }}'
            sequence:
              - service: light.turn_on
                target: !input target_lights
                data:
                  brightness_step: '{{ dimm_step }}'
              - delay:
                  milliseconds: '{{ dimm_delay }}'
    # DIMM DOWN
    - conditions:
        condition: and
        conditions:
          - condition: trigger
            id: "dimm"
          - "{{ 1 <= trigger.payload <= 7 }}"
      sequence:
        - repeat:
            count: '{{ dimm_steps }}'
            sequence:
              - service: light.turn_on
                target: !input target_lights
                data:
                  brightness_step: '{{ -dimm_step }}'
              - delay:
                  milliseconds: '{{ dimm_delay }}'

Updated to use knx.telegram trigger released in HA 2024.6

@farmio This works absolutely perfectly, I can‘t thank you enough. Implementing this myself would have been hell.

I have a question though: how can I alter this to mimic the KNX behaviour „don‘t turn off through relative dimming“? I.e. when I dim down I want the light to stay at the lowest brightness instead of turning off. The Home Assistant UI also behaves this way.

@bob-lobster I think it depends on the target entity. Not every one turns off on brightness = 0 - or is configurable (like most KNX actuators).
If you can't set it in the target integration, try modifying line 134 to set an absolute brightness based on max(current_brightness - dimm_step, 1) or something like that.

Thanks I changed it to

brightness: “max(state_attr('light.bed', 'brightness')-dimm_step, 2)“

With absolute brightness 1 they would be at 1 % and on in HA but the bulbs were off.

They are Hue bulbs via Skyconnect actually but I couldn‘t figure out how to change the behaviour there.

Hi,

thank you for this blueprint code.
It works great for me. I am using an MDT KNX Wall Switch with an HUE ceiling light.
I could set those paramters for my claims.

Is it possible to add one more slider for an inital value?

Right now i switch on and off on a plus and a minus button with a short tap and same with dimming the light, but with long taps.
I would like to switch on the light everytime to 100% by Default. Right now it turns on by default with the last value

Cheers
Christian

@CyberChris79 Hi 👋! IMO turn on value should be handled by the actuator - most provide configurations for that.

The intention of this blueprint is to provide a reference for the usage of Knx actions and triggers - for other blueprint creators. So I don't plan to add any features to it.
Feel free to fork it and modify to your needs.
Or have a look for existing forks - maybe the thing you are looking was already done by someone else.