Output relative brightness

This action changes the brightness of an output port on an LCN module by a relative amount. Use a positive value to brighten and a negative value to dim, for example to step a light up by 30%.

Using this action from the user interface

If you prefer building automations and scripts visually, Home Assistant walks you through this action step by step. You pick what to target, tweak a few options, and save. No YAML knowledge required.

To change the relative brightness of an output port from an automation or a script:

1. Go to Settings > Automations & scenes.
2. Open an existing automation or script, or select Create automation > Create new automation.
3. If you’re setting up a new automation, add a trigger in the When section. Scripts don’t need a trigger. They run when something else calls them.
4. In the Then do section, select Add action.
5. From the search box, search for and select LCN: Output relative brightness.
6. Select the LCN module or group in the Device field, choose the Output port, and set the Brightness change.
7. Select Save.

This action does not support targets. Instead, you select the LCN module or group through the Device field.

Options in the UI

Using this action in YAML

If you work directly in YAML, or you want to know exactly what Home Assistant does under the hood, this section has the technical reference. It lists the field names you use in YAML, their types, and which ones are required.

In YAML, refer to this action as lcn.output_rel. A basic example looks like this:

action: lcn.output_rel
data:
  device_id: 91aa039a2fb6e0b9f9ec7eb219a6b7d2
  output: output1
  brightness: 30

This increases the brightness of output port 1 by 30%.

Options in YAML

Try it yourself

Ready to test this? Open Developer tools > Actions, search for this action, fill in the fields, and select Perform action. You see what happens on your actual entitiesAn entity represents a sensor, actor, or function in Home Assistant. Entities are used to monitor physical properties or to control other entities. An entity is usually part of a device or a service. [Learn more] without writing a line of YAML.

Still stuck?

The Home Assistant community is quick to help: join Discord for real-time chat, post on the community forum with the action you’re calling and what you expected to happen, or share on our subreddit /r/homeassistant.

Related actions

These actions work well alongside this one:

• Output absolute brightness: Sets absolute brightness of output port in percent.

• Toggle output: Toggles output port.

• PCK: Sends an arbitrary PCK command.