End of support notice: On May 20, 2026, AWS will end support for AWS IoT Events. After May 20, 2026, you will no longer be able to access the AWS IoT Events console or AWS IoT Events resources. For more information, see [AWS IoT Events end of support](https://docs.aws.amazon.com/iotevents/latest/developerguide/iotevents-end-of-support.html).

# BatchUpdateDetector example for an HVAC system in AWS IoT Events
<a name="iotevents-examples-hvac-batch-update-detector"></a>

In this example, `BatchUpdateDetector` is used to change operational parameters for a working detector instance.

Efficient HVAC system management often requires batch updates to multiple detectors. This section demonstrates how to use AWS IoT Events's batch update feature for detectors. Learn to simultaneously modify multiple control parameters, update threshold values, so that you can adjust response actions across a fleet of devices, improving your ability to manage large-scale systems effectively.

CLI command used:

```
aws iotevents-data batch-update-detector --cli-input-json file://areaDM.BUD.json
```

File: `areaDM.BUD.json`

```
{
  "detectors": [
    {
      "messageId": "0001",
      "detectorModelName": "areaDetectorModel",
      "keyValue": "Area51",
      "state": {
        "stateName": "start",
        "variables": [
          {
            "name": "desiredTemperature",
            "value": "22"
          },
          {
            "name": "averageTemperature",
            "value": "22"
          },
          {
            "name": "allowedError",
            "value": "1.0"
          },
          {
            "name": "rangeHigh",
            "value": "30.0"
          },
          {
            "name": "rangeLow",
            "value": "15.0"
          },
          {
            "name": "anomalousHigh",
            "value": "60.0"
          },
          {
            "name": "anomalousLow",
            "value": "0.0"
          },
          {
            "name": "sensorCount",
            "value": "12"
          },
          {
            "name": "noDelay",
            "value": "true"
          },
          {
            "name": "goodToGo",
            "value": "true"
          },
          {
            "name": "sensorId",
            "value": "0"
          },
          {
            "name": "reportedTemperature",
            "value": "0.1"
          },
          {
            "name": "resetMe",
            "value": "true"
          }
        ],
        "timers": [
        ]
      }
    }
  ]
}
```

Response:

```
{
    An error occurred (InvalidRequestException) when calling the BatchUpdateDetector operation: Number of variables in the detector exceeds the limit 10
}
```