Logic and Controls Design

It is interesting to me how many people involved in the design and coding of PLC and SCADA programs have no formal training (or any apparent understanding) of the simple rules of combinational and sequential logic. The basics of AND, OR, NOT and minimization techniques that are offered in any Logic 101 course are completely unknown to these people and yet they want to create complex applications to do real-functions like controlling water treatment plants or manufacturing lines. It 'bloggles' the mind!

If you are responsible for such teams. Make sure that each member of your design and programming teams has a working understanding of these basic elements of design and uses them consistently. It will pay big dividends for your margin, your customer's satisfaction and ultimately minimize life-cycle costs for the system. Oh and did I mention about the benefits when it comes to adding functionality or make minor changes?

Remember that the plant operator 'sees' the process primarily through the Operator Interface that you provide. You need to do everything humanly possible to provide a clear accurate window of what is going on in those tanks, pipes, reactor, mixers and whatever other unit processes are involved, but that is the subject for another posting.