I can remember back to when I was in elementary and at the time I saw the janitor repairing lights in the school, and I thought to myself I may like to do that one day. Who knew that I would one day enter into the trades? I started my electrical career in 1985 as an apprentice for a small electrical firm in southern Alberta. I felt privileged to be with a small firm as it requires everyone to help out on every project, be it a grass roots facility or just maintenance. Another advantage is that I was exposed to not only Industrial/Commercial but also the Oil and Gas Industry.
I can remember going to the local Distillery for maintenance and was amazed at the size of the control room. Inside was a 15-20 foot long, floor to ceiling, control cabinet made of sheet steel with depictions of facility painted/stenciled onto it. The process was stenciled onto the horizontal portion of the panel. Indicating lights were used to inform the operator if the conveyor or motor was on or off. There were analog meters and pneumatic controllers with the red bar that moved up and down to indicate level or pressure. Switches and pushbuttons for each motor or slide gate covered the remainder for the panel. Getting access to the back of the panel revealed the large quantity of wires and pneumatic tubing required to operate the facility. This was the same for the older gas plants. One simple fact was that if you wanted to find the control room just look for where all the conduits and pneumatic tubing converged on a single location. Most safety and control devices such as level, pressure, and temperature switches were wired to individual relays. These relays were used as interlocks, which is to say that a motor or valve cannot operate unless everything is in normal condition. Alarms were indicated using an annunciator panel or light box. Simply put, it was a large panel with multiple lights that would shine through a frosted cover with etched lettering as to what the alarm is.
As technology progressed automated control systems such as Distributive Control Systems (DCS) Programmable Logic Controller (PLC) came into play replacing the relay panels, annunciator boxes and the pneumatic controllers, that filled the control room with as little as one operator station. This station could be a touchscreen display or a PC with up keyboard, mouse and one monitor. Gone were the dinosaur frosted covers with etched lettering.
First steps were to have this control system located in one central location. All field wiring would terminate at this panel. There is no need to bring any pneumatic tubing back to this location as the controllers became part of the control system and only an electrical signal on how much to open the valve is sent to the valve itself. Air is still used to open the valve as it can provide more torque to complete the work.
The next step was to relocate part of the control system to local areas or skids. This allows for a reduction in the amount of wires installed to the main control system.
Instruments themselves have advanced over time as well. Smart meters can now give you a baseline when installed as to how they are performing. This can be monitored over time and allow a maintenance program to monitor the condition of the valve to gauge when a repair is required before a failure happens.
Operator stations have evolved with the use of multiple screens or monitors being connected to a single PC. This allows the operator to have different aspects of the process being displayed without having to change the screen view.
Communication has also advanced from having an automated call out system that would phone an operator with an alarm that something is wrong at the site to allowing the operator to log in from home to view the facility. Going one step further, the operators for a major facility now may not actually have to be on site. A remote operator station/ ghost station can be located in a place like downtown Calgary and have full control of the plant. There is still a physical presence on site though, through the maintenance group. Who knew it was possible to control a plant remotely, hundreds or maybe thousands of kilometers away, years and years ago?
Reminiscing growing up as a child in southern Alberta, and watching someone replace lights – and today, we still replace lights, but perhaps not the with same kind of bulbs. It’s amazing to see the advancements made in the course of my career alone. The developments in the industry over the years have allowed for improved systems & efficient processes. It is exciting to see where the next innovations will take us and how our children will think the times have changed.