Plant automation has historically been the responsibility of the control system engineer—you know, the instrumentation guy, the DCS guy, the PLC and HMI guy. Interfaces were straightforward with discrete I/O and 4-20 mA; maybe an occasional RS-232 serial interface. Troubleshooting tools consisted primarily of a multimeter and a programming terminal. This mostly defined the world of our beloved control system engineer.
But the plant automation world has exploded lately with the adaptation of many technologies borrowed from other industries. Proprietary networks have given way to Ethernet. Standalone computers are being replaced with fault-tolerant servers running many images of virtualized machines. Thin-client workstations are rapidly replacing bulky computer-based operator stations. Big Data is gaining a stronger foothold in plant automation at lightning speed. And network security is paramount to having a safe and robust automation system for plant operations. The control system engineer of days gone by might be ill-equipped to adequately support these contemporary elements of a control system. Adaptation will be necessary to survive.
In the field of industrial automation, the role of the control system engineer is quickly morphing into a more demanding role in order to address the ever-changing operational technology on the plant floor. We are in an era where these engineers are evolving into much more versatile team members who have to reach beyond the highly specialized and purpose-built industrial equipment and begin embracing the influence of information technology (IT). A more appropriate descriptor for this engineer might be the operational technology (OT) engineer.
Cloud-based systems, mobile app integration, and the Industrial Internet of Things (IIoT) are changing the way we design and support systems. We have been interconnecting disparate systems and devices for decades on the plant floor, but it has only been recently that the focus has shifted to the agility of producing actionable intelligence. This is the essence of IIoT, and it takes a different breed of engineer to navigate the complex integration of operational and information technology required to facilitate this agility.
The OT engineer needs to have a working understanding of server virtualization, routing and switching, firewalls, storage area networks, relational databases and VPN tunnels along with the traditional elements of instrumentation, control and HMI platforms. This knowledge base is key to unlocking the valuable data embedded in today’s control systems from the most fundamental field device up through the interfaces to the company’s business systems—spanning a manufacturing plant’s entire operation, including process, packaging, utilities and building services (HVAC, security, fire alarm).
These tools are necessary to troubleshoot and maintain contemporary automation systems. Let me give you a couple of very recent real-world examples from the plant floor.
Example 1: A new client contacted us saying they were having repeated problems with an e-stop system on their process and wanted our engineer to “figure out where in the PLC program” this was causing their process line to shut down. After looking through the program as requested, our engineer explained to the Plant Manager that there was nothing in the program that he could see causing the e-stops. When the plant manager insisted it had to be something in the PLC (indirectly questioning our engineer’s competence), we pushed back, explaining that it had to be something else in the system, and saying we needed to visit the site. While on-site at the plant, one of our OT engineers traced the e-stop process line shutdown to an eight-port unmanaged network switch (hanging in the air supported by the Cat. 5e cables plugged into it) that was locking up and causing variable-frequency drives (VFDs) with Ethernet interfaces to stop running due to a “loss of communications” error.
Example 2: An existing client wanted us to look at several 2017 projects at one of its facilities that we had not yet worked at. One project involved control and HMI upgrades. While at the plant, we suggested the current standalone HMIs be incorporated into their existing client-server SCADA. The plant engineer said, “No, we think we’re maxing out the server because our screen updates and response times to operator actions have gotten slower.” We surveyed their current system and found their entire control network to be a flat network, with numerous daisy-chained unmanaged switches. We’re still looking further into identifying other sources of the sluggish control and SCADA system responses, but we think we’ve already uncovered one culprit.
Traditional knowledge and experience on legacy control systems for manufacturing automation is valuable in today’s plant environment. Let’s not let it walk out the door. Use it as a base platform and layer on top of it training on the newer technologies used in contemporary manufacturing automation systems. Additionally, create a mentoring program where the seasoned control system engineer pairs with the newer engineers already familiar with the new technologies and help create the new-age team of OT engineers.
Steve Malyszko, P.E., is president and CEO of Malisko Engineering Inc., a certified member of the Control System Integrators Association (CSIA). See Malisko Engineering’s profile on the Industrial Automation Exchange.
