Start an alert on a warning device

Use this action to start a full alert on a Zigbee warning device, such as a siren. The device alerts the surrounding area with sound and, optionally, a flashing strobe for a set duration. You identify the device by its IEEE address. A common use is to sound a siren when a motion sensor detects someone while you’re away.

Only users with administrator rights can run this action.

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 start an alert 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. Search for and select Warning device starts alert.
6. Set the device and, optionally, the mode, strobe, level, duration, and strobe details.
7. 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 zha.warning_device_warn. A basic example looks like this:

action: zha.warning_device_warn
data:
  ieee: "00:0d:6f:00:05:7d:2d:34"
  duration: 10

This sounds the siren for 10 seconds.

Options in YAML

Good to know

• If both the mode and the strobe are set to 0, the duration is ignored and nothing happens.
• The exact sound for each mode depends on the device.

More examples

Real scenarios where this action shows up in automations and scripts. Copy any example and adapt it to your setup.

Automation: sound the siren when motion is detected while away

Start the siren for 30 seconds when a motion sensor turns on and nobody is home.

- alias: "Sound the siren on motion while away"
  triggers:
    - trigger: state
      entity_id: binary_sensor.hallway_motion
      to: "on"
  conditions:
    - condition: state
      entity_id: group.family
      state: "not_home"
  actions:
    - action: zha.warning_device_warn
      data:
        ieee: "00:0d:6f:00:05:7d:2d:34"
        duration: 30

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:

• Make a warning device squawk: Emits a short audible and visible pulse on a Zigbee warning device.