How to Build an Edge Data Pipeline for PLCs at the Edge
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In the oil and gas, manufacturing, and utilities sectors, integrating edge computing with Programmable Logic Controllers (PLCs) is becoming crucial. The need for real-time data processing and reduced latency drives the adoption of technologies that enhance operations directly at the edge.
This blog will walk you through setting up an edge data pipeline using Prescient Designer (a edge data pipeline solution), focusing on connectivity and dynamic configurations.
Representative Edge Data Pipeline Dashboard
The data pipeline dashboard in Prescient Designer is designed primarily for operations teams. It provides a clear, user-friendly interface that highlights key aspects of your edge data pipeline, particularly in interfacing with PLCs at the edge.
On the left side of the dashboard, you'll find a visual representation of your system’s connectivity. For example, it shows an edge gateway with a tick mark that indicates a connected device. This connectivity status is an out-of-the-box feature provided by Prescient Designer, enabling immediate insights into the operational health of your network.
With real-time monitoring, the dashboard ensures that any issues, such as a disconnected cable, are instantly identified, allowing for quick corrective action and ensuring continuous operations.
Operational Dashboard Features and System Configurability
The operational dashboard in Prescient Designer is the nerve center for managing edge data pipelines, offering a highly glanceable view of the entire system.
Key features include:
Visual Representation of Connections: If an edge gateway is connected to multiple PLCs, the dashboard visually represents these connections, including real-time connectivity indicators between the gateway and each PLC.
Real-time Connectivity Indicators: For example, if an ethernet cable becomes disconnected, the dashboard will immediately update to reflect this issue, providing a real-time indicator specific to that PLC.
Real-time Signal Monitoring: The panels on the right side of the dashboard display different real-time signals captured from PLCs or other data sources, whether at the edge or in the cloud. These signals can come from either or both sources, ensuring continuous monitoring and effective data management.
Gateway Selection and Data Frequency Adjustment: The dashboard includes a form that allows users to:
- Select the Desired Gateway: Choose which gateway to interface with.
- Adjust Data Transmission Frequency: Set how often data is sent from the edge to a time-series database in the cloud.
Configurability of the Edge System
Adapting to operational demands requires a flexible system. Prescient Designer allows for dynamic adjustments to how data is interfaced and managed within the system.
Here’s how to effectively manage these configurations:
Select the Desired Gateway: Navigate through the dashboard to choose the gateway you wish to configure.
Modify the Pulling Frequency: Adjust the frequency at which data is sent from the edge to the cloud. For example, you might start with a pulling rate of 300 seconds, but for more immediate data transfer, you could reduce it to 10 seconds.
Apply Changes Instantly: As soon as you submit the changes, Prescient Designer sends a message to the edge device to update the pulling interval dynamically. This demonstrates the system’s ability to swiftly adapt to new data handling requirements.
Dynamic Configuration Capabilities
Prescient Designer supports dynamic adjustments beyond just the pulling rate:
Tag Definition and Update Rates: Not only can the pulling rate be changed, but entire tag definitions can also be updated dynamically. For instance, different tags can be set to update at different rates depending on the specific needs of your operation.
Comprehensive Dashboard Overview: You can expand the dashboard to include a summary of all devices connected to the PLCs, providing an overview of their statuses and ensuring that all configurations are optimized for operational efficiency.
Pro Tip: Regularly review the system configuration to optimize data flow and adapt to operational changes. This approach not only enhances efficiency but also ensures data integrity and reliability.
How to Setup Data Pipeline Workflow at the Edge
Setting up an effective workflow with Prescient Designer involves managing the seamless transfer of data from PLCs to the cloud. This process is made efficient by the integration of various devices and protocols within Prescient Designer. Here’s how the workflow is structured:
Deployment of the Edge Data Pipeline: Prescient Designer enables the deployment of a self-flow based on Node-RED, which is running directly on the edge gateway. This setup is crucial for capturing and processing data from connected PLCs.
Connecting to PLCs: The edge gateway in Prescient Designer is typically connected to PLCs using various protocols like Modbus, MQTT, Profinet, and OPC UA. For instance, a Modbus connector may be used to capture data from a PLC every second.
Data Decimation and Processing:
Pulling Rate Adjustment: The pulling rate, which is set from the dashboard, determines how frequently data is captured and processed. In this case, the connector is set to capture data every second, but this can be decimated to a different rate as specified in the dashboard.
Data Validation and Transformation: After decimation, the data is validated and transformed into a schema that is compatible with the time-series database, such as InfluxDB, which is located in the cloud.
4. Data Transmission and Networking:
Output to the Cloud: The processed data is transmitted to the cloud, ensuring that only the relevant information is stored and analyzed.
Automatic Network Configuration: Prescient Designer’s automatic networking capabilities allow seamless communication between devices at the edge and the cloud. This feature ensures that the data flow is transparent to the user, with device-to-device connectivity managed automatically.
5. Debugging and Monitoring:
Real-Time Data Monitoring: The workflow allows for real-time monitoring and debugging of the data being transmitted between the edge and the cloud. This feature is crucial for ensuring data integrity and system reliability.
6. Dynamic Configurability:
Real-Time Adjustments: One of the key strengths of Prescient Designer is its ability to make real-time adjustments to the system configuration. For example, changing the pulling rate from 300 seconds to 10 seconds can be done instantly, resulting in a significant increase in the number of data points collected.
Operational Flexibility: This dynamic configurability is particularly valuable in environments where installations are not uniform, such as when different generations of equipment are in use. Prescient Designer allows for different configurations to be applied to different machines or sites, ensuring that the system can adapt to a variety of operational needs.
Conclusion
Building an edge data pipeline for PLCs is a strategic move to enhance operational efficiency in key industries. By leveraging Prescient’s Node-RED for Enterprise, your business can ensure robust and adaptable edge computing setups.
For visual aids and detailed guidance, refer to the complete video tutorial.