Pulse effect

The Pulse effect action runs a flash effect on LIFX lights by changing to a color and back. It’s a good way to get someone’s attention, for example to flash the hallway light when the doorbell rings or when a door is left open.

This is a software effect, which means Home Assistant drives each color change over your network. It works on every LIFX light, including white-only models. When the effect finishes, each light returns to the color and power state it had before the effect started.

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 run the pulse effect 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 Pulse effect.
6. Select what you want to control. Under By target (see Targets), pick the area your LIFX lights are in (like your living room or bedroom). You can also select a floor, a device, a specific entity, or a label.
7. Select Mode to choose how the color changes, then pick the flash color with either Color name or RGB color.
8. Optional: set Cycles to flash more than once, and Period to make each flash faster or slower.
9. Select Save.

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 lifx.effect_pulse. A basic example looks like this:

action: lifx.effect_pulse
target:
  entity_id: light.office
data:
  color_name: "red"
  mode: breathe
  cycles: 3

This makes the office light breathe red three times, then return to its previous color.

Options in YAML

Targets of the action

This action requires a target. The target is the object of the action. You can point the action at a single entityAn 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], a device, an area, a floor, or a label, and Home Assistant will run the action on every matching light entity behind that target.

• Entity: one specific light entity, such as light.living_room.
• Device: every light entity that belongs to a device.
• Area: every light entity in a room or area.
• Floor: every light entity on a floor.
• Label: every light entity that shares a label.

You can also select different target types in one action. For example, you can add a specific entity and an area as targets in the same action to run the action on both of them at once.

Good to know

• This action only works on lights that belong to the LIFX integrationIntegrations connect and integrate Home Assistant with your devices, services, and more. [Learn more]. When you target lights by entity and none of them is a LIFX light, Home Assistant reports an error: “The targets of action lifx.effect_pulse include no LIFX light”. When you target an area, floor, device, or label that holds no LIFX light, nothing happens and no error is returned.
• The pulse effect works on every LIFX light, including white-only models such as the LIFX White and Mini White.
• If you don’t set a color, each light flashes using its own current color, so the flash is only visible when you change the brightness or the mode.
• Because this is a software effect, Home Assistant sends each color change over your network. Very short periods across many lights can look less even than a firmware effect such as Move effect.
• Starting a pulse effect replaces a software effect that’s already running on the same light, such as Color loop effect. It doesn’t clear a firmware effect such as Move, Flame, Morph, or Sky, so run Stop effect first if one of those is running.
• To end the effect before it finishes all its cycles, use Stop effect.
• You can also start this effect with its default options from the regular light.turn_on action by setting its effect to effect_pulse. Use this dedicated action when you want to control the color, mode, period, or number of cycles.

Try it yourself

Ready to test this? Open Settings > 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.

More examples

Real scenarios where this action shows up in automations and scripts. Copy any example and adapt it to your setup. In the visual editor, select the UI options listed in the example or paste the YAML code.

Automation: flash the hallway light when the front door opens

When the front door opens, flash the hallway light blue twice so you notice it from another room.

• Trigger: Front door opened (binary_sensor.front_door)
• Action: Pulse effect
  • Target: Hallway light (light.hallway)

alias: "Flash the hallway light when the front door opens"
triggers:
  - trigger: state
    entity_id: binary_sensor.front_door
    from: "off"
    to: "on"
actions:
  - action: lifx.effect_pulse
    target:
      entity_id: light.hallway
    data:
      color_name: "blue"
      mode: breathe
      cycles: 2

Automation: flash the office light when the washing machine finishes

When the washing machine power drops below 5 W, flash the office light green and send a notification to your phone.

• Trigger: Washing machine power below 5 W (sensor.washing_machine_power)
• Action: Pulse effect
  • Target: Office light (light.office)
• Action: Send a notification message
  • Target: My Device (notify.my_device)

alias: "Flash the office light when the washing machine finishes"
triggers:
  - trigger: numeric_state
    entity_id: sensor.washing_machine_power
    below: 5
    for: "00:02:00"
actions:
  - action: lifx.effect_pulse
    target:
      entity_id: light.office
    data:
      color_name: "green"
      mode: breathe
      cycles: 5
      period: 2
  - action: notify.send_message
    target:
      entity_id: notify.my_device
    data:
      message: >
        The washing machine has finished.

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

Explore related actions:

• Color loop effect: Run an effect on LIFX lights that loops colors around the color wheel.

• Stop effect: Stop a running effect on LIFX lights.

• Set state: Change the color, brightness, and power of a LIFX light in a single step.