Process Controls have come a long way since the mechanical relay panels used in factories, refineries, chemical plants, and pipelines. These panels occupied a lot of space, and required a certain skill to maintain both the relay panel, its contents, and the drawings. The drawings were, back then, the program. The relay panels were laid out very well, and were wired neatly, a lost art today. A common nylon “zip-tie” today, was “wax thread” yesterday, keeping all the wires neatly gathered, and routed to their termination points. As technology in this field evolved, the relay panels did as well. Now you see the same neat panels, smaller, in some cases to say the least, serve the same function, but are safer to work in, and offer more functions than ever before.
In comes the Programmable Logic Controller (PLC) hardware, the software, and Human Machine Interface equipment, not to mention the latest din rail mounted “safe” terminals and peripheral components that make up a control cabinets contents. The skill set, now, is basically the same, but with a twist. The “Integrator” as we are called, has to know how to navigate thru a logic editor, know the different programming languages, and know how to transform the process controls ideas from paper to the software. The versatility of today’s PLC is almost endless, and mapping the incoming field signals to a local screen for display, DCS systems, or upper level SCADA system is at the integrators finger tips.