Guidance on how to connect 3rd party PLC to IoT Hub

Hello Zach Pertee

Here’s how you can connect a 3rd party PLC (Programmable Logic Controller) to Azure IoT Hub, with references to public documentation and resources:

1. Use an Industrial Gateway or IoT Edge Device

Most 3rd party PLCs do not natively support direct connection to Azure IoT Hub. You typically need an industrial gateway or an IoT Edge device that can:

• Communicate with the PLC using industrial protocols (e.g., Modbus, OPC UA, S7, etc.)
• Translate PLC data to a protocol supported by IoT Hub (MQTT, AMQP, HTTPS)
• Securely forward data to Azure IoT Hub

Reference:

• Microsoft Learn:
• https://free.blessedness.top/en-us/azure/iot-operations/manage-mqtt-broker/howto-broker-mqtt-client-options
• https://free.blessedness.top/en-us/azure/iot-operations/discover-manage-assets/overview-opc-ua-connector
• https://free.blessedness.top/en-us/azure/iot-edge/how-to-deploy-modules-portal

2. Register the Gateway/Device in IoT Hub

• Create a device identity for your gateway or edge device in the IoT Hub device registry.
• Use the generated credentials (symmetric key, X.509 certificate, or TPM) to authenticate the device.

Reference:

• Microsoft Docs:
• https://www.linkedin.com/pulse/step-by-step-guide-installing-opc-publisher-azure-iot-kevin-hilscher/

3. Configure Data Flow

• Set up the gateway or IoT Edge device to poll or subscribe to data from the PLC.
• Configure the gateway to send telemetry data to IoT Hub.
• For OPC UA-based PLCs, you can use the Azure IoT Edge OPC Publisher module.

5. Security and Management

• Use IoT Edge for secure, managed connectivity and module deployment.
• Leverage Azure IoT Central or IoT Hub for device management, monitoring, and command/control.

Hope it helps.

Please share your methodology and error trace for further assistance.

Thank you.