Use the following workflow to deploy and test your Azure Security Center for IoT security agents:
1. Enable Azure Security Center for IoT service to your IoT Hub
2. If your IoT Hub has no registered devices, Register a new device.
3. Create an azureiotsecurity security module for your devices.
Azure Security Center for IoT makes use of the module twin mechanism and maintains a security module twin named azureiotsecurity for each of your devices.
Note: To manually create a new azureiotsecurity module twin for a device use the following instructions:
1. In your IoT Hub, locate and select the device you wish to create a security module twin for.
2. Click on your device, and then on Add module identity.
3. In the Module Identity Name field, enter azureiotsecurity.
4. Click Save.
Reference:
https://docs.microsoft.com/en-us/azure/asc-for-iot/quickstart-create-security-twin