Create and Clear Alarms

Monitor a temperature sensor and automatically create and clear alarms when readings go outside an acceptable range. This recipe uses importable alarm rule configurations so you can examine the logic and adapt it for your own scenario.

Assume your refrigeration equipment has a temperature sensor that periodically publishes telemetry to ThingsBoard. The normal operating range is 2 °C – 5 °C. Outside this range, the condition is treated as abnormal:

• Create an alarm when temperature drops below 2 °C or rises above 5 °C.
• Clear the alarm automatically when temperature returns to the normal range.

This pattern applies to cold storage, food logistics, and industrial refrigeration monitoring.

Review the Alarm rules documentation before proceeding — it covers alarm creation, trigger conditions, and the alarm lifecycle.

You also need a device to test with. Use an existing device or create a new one:

1. Navigate to Entities ⇾ Devices.
2. Click + Add device ⇾ Add new device.
3. Set Device name to Thermometer and Device profile to thermostat.
4. Click Add.

Two alarm rules cover the two failure conditions:

Each rule is evaluated on every incoming telemetry message: the value is read, compared against the create and clear conditions, and the alarm is created, updated, or cleared accordingly.

1. Download the alarm rule configuration file: high_temperature_alarm_rule.json
2. Go to Alarms ⇾ Alarm rules.
3. Click + Add alarm rule ⇾ Import alarm rule.
4. Upload the downloaded file.
5. Specify your device or device profile as the target entity.
6. Click Add.

1. Download the alarm rule configuration file: low_temperature_alarm_rule.json
2. In Alarms ⇾ Alarm rules, click + Add alarm rule ⇾ Import alarm rule.
3. Upload the downloaded file.
4. Specify your device or device profile as the target entity.
5. Click Add.

Publish test telemetry values using Check connectivity or the curl commands below.

Trigger the High temperature alarm — publish a value above 5 °C:

curl -v -X POST \
--header "Content-Type: application/json" \
--data '{"temperature": 7}' \
http://thingsboard.cloud/api/v1/$ACCESS_TOKEN/telemetry

Clear the High temperature alarm — publish a value in the normal range:

curl -v -X POST \
--header "Content-Type: application/json" \
--data '{"temperature": 4}' \
http://thingsboard.cloud/api/v1/$ACCESS_TOKEN/telemetry

Trigger the Low temperature alarm — publish a value below 2 °C:

curl -v -X POST \
--header "Content-Type: application/json" \
--data '{"temperature": 1}' \
http://thingsboard.cloud/api/v1/$ACCESS_TOKEN/telemetry

Clear the Low temperature alarm — publish a value in the normal range:

curl -v -X POST \
--header "Content-Type: application/json" \
--data '{"temperature": 4}' \
http://thingsboard.cloud/api/v1/$ACCESS_TOKEN/telemetry

After each step, check the alarm state on the Alarms page, on the device’s Alarms tab, or on a dashboard widget.

• Alarm rules — full configuration reference
• Alarm rule tutorials — step-by-step examples for thresholds, duration, schedules, and more