GTH: Multi-Vendor PLC Integration and Software-Defined Automation

On November 12, 2026, Plant Engineering and Control Engineering published an interview with George T. Hall Company (GTH), the systems integrator that won the under-$10 million revenue category in the 20th edition of the System Integrator of the Year award. Here we set the recognition aside and focus on the technical content, which is more useful to those working in automation. Note: this analysis is based only on the first part of the interview, because the page I read was truncated.

The Hyperion MBR Pilot Facility Case

The project concerns the Hyperion pilot facility in Southern California, which supports the Pure Water Los Angeles program. The challenge was to bring three membrane bioreactor (MBR) systems, supplied by different manufacturers, into one coordinated facility, each with its own PLC, control logic and operating requirements.

GTH did not replace or redesign the vendors' control systems. It chose a centralized architecture, with a main PLC panel acting as the master controller. The activities described include:

• process sequencing logic, interlocks, alarms and performance monitoring across the three systems;
• a communication link to the supervisory environment already in place at the plant, with standardized data structures and uniform alarm handling for consistent reporting;
• flow, level, pressure and analytical instrumentation, with calibration and loop checks;
• FAT and SAT, commissioning, tuning, operator training and documentation.

According to GTH, connecting the equipment is only part of the challenge; the rest of the sentence was not visible on the page I read.

Why This Is a Useful Example

The problem is common in brownfield projects and with packaged machines: every skid arrives with its own logic, tags and alarms. The risk is a plant that works in pieces but is hard to operate and analyze. The approach described, with a master PLC above the vendors' logic and a common data and alarm model, avoids touching software already validated by the manufacturers and brings consistency where it really matters: sequences, interlocks and reporting.

Connecting the equipment is only part of the challenge: the value lies in the common model of data, alarms and sequences.

The Software-Defined Front

GTH has earned Schneider Electric EcoStruxure Automation Expert (EAE) certification and has dedicated two engineers to the platform. A client project based on EAE is described as "on track for completion in 2026". EAE represents the software-defined, hardware-independent approach to automation; it is based on the IEC 61499 standard, although the page does not state this. Results from this project have not yet been reported, so it is too early to judge its practical impact.

Other Points That Emerged

The interview also mentions the Chino Hills 1,2,3-TCP Treatment upgrade project in the water and wastewater sector, whose details I have not read. GTH also runs a UL-certified panel shop in Anaheim, California, and in its application emphasized continuing training, manufacturer certifications and long-standing client relationships.

Practical Takeaways

For those tackling integration of heterogeneous skids:

• define a common data and alarm model from the start, before writing the master logic;
• leave vendors' controllers untouched when they are already qualified, and coordinate them from a higher level;
• plan instrumentation, loop checks, FAT/SAT and training together, because integration does not end with communication;
• approach software-defined platforms with caution: wait for real results from the first projects before drawing conclusions.