The solution
To bridge these separate systems, Blendtech chose to build their system on Opto 22’s groov EPIC. It provided all the functions they needed in a single package—secure connectivity, data processing, and storage—which meant they didn’t need a PC or additional hardware to complete the design, and it was backed by excellent user documentation and free customer support.
With groov EPIC, Blendtech was able to present their customer with a reliable data aggregation solution that significantly reduced the cost of API 2350 compliance.
Here’s how they did it.
Step 1 involved bridging the networks. At its heart, groov EPIC is an industrial controller capable of high-speed I/O operations, but Blendtech focused on using its connectivity and processing power as a secure network gateway.
The groov EPIC processor (GRV-EPIC-PR1) has two completely segregated network interfaces, so that trusted and untrusted networks can be isolated. This segregation solved the basic problem of bridging the corporate and control networks without permitting unregulated traffic between them. The controller fit comfortably into the existing control cabinet using a zero-I/O chassis (GRV-EPIC-CHS0), a small-footprint housing (5.36” x 3.54”) for applications that don’t require I/O operations.
Step 2 was all about retrieving and normalizing data. While legacy PLCs may be capable of communicating using various industrial protocols, they are usually unable to interface with modern IT systems directly. With groov EPIC on the network, however, Blendtech could build a custom data processing interface for the TAS directly into the controller using the embedded Node-Red Internet of Things connectivity software. Node-Red boasts a large library of functions for connecting data sources, including drivers for many popular databases.
The ultimate goal was to provide time-sequenced data as a series of Modbus registers that the master PLC could read from the groov EPIC processor. That wasn’t the native format of the data in the TAS, however and, depending on which loading rack the data originated from, various operations had to be performed to achieve this consistent format.
Blendtech designed event triggers to recognize when data in the TAS had been updated, as well as the source of the data. Then they invoked logic to sequence, format, and scale appropriately for the specific data source. Blendtech used Node-Red to handle all of this, with custom formatting logic in embedded JavaScript functions.
Step 3 focused on moving data into the site historian. With 6 GB available on a fault-tolerant solid-state drive (SSD), the EPIC could also serve as the temporary storage location for everything it retrieved from the TAS, ensuring no additional hardware was necessary to complete their system.
After retrieval and processing in Node-Red, data was written to the groov EPIC’s internal hardware memory map, where it could be accessed via Modbus/TCP requests from the master PLC. Once there, the historian could poll the PLC at regular intervals to add this data to the site archives.
Blendtech also took advantage of groov EPIC’s built-in touchscreen and embedded groov View server to design a basic human-machine interface for controller and network health monitoring. Since groov View is mobile-ready, the status of the controller can be viewed from any smart device or computer connected to the network, using the built-in user access controls to maintain security.
The future
Ultimately, Blendtech was able to meet their customer’s goal, delivering a system to automate inventory reconciliation at a fraction of the cost of the typical alternatives. With significantly less manpower, they can audit their transaction history every hour instead of every day, improving their accounting granularity and increasing confidence that product is being safely managed.
What’s next? With around 30 similar installations in Canada and 120 across the U.S., Blendtech continues to present their reconciliation system to more potential customers. By installing the full Ignition Gateway and SQL-Bridge module on the EPIC, Blendtech plans to design even more robust transactional logic into their TAS database monitoring.
They are also expanding their portfolio of custom Industrial Internet of Things applications built on groov EPIC. For example, they are developing a traffic management system for use in distribution terminals. Using the EPIC’s I/O control functions, the system will control high-visibility lane and wait-time indicators to optimize the flow of tanker trucks through loading racks.