This article was printed in CONTROL's October 2009 edition.
By Contributors to The Process Automation Usability Project
One of the most recent additions to Controlglobal.com is The Process Automation Usability Project. This is a forum where visitors can weigh in and share ideas on process topics such as design, implementation, maintenance, operations, planning and security. These subject-specific forums have gathered an interested following with insightful commentary and ideas. Here we bring you some of the most recent discussion on the subject: "Shouldn't process automation (PA) technology be easier to engineer, implement, operate and maintain?"
John McConnell, a controls engineer says: "There is just a lot involved in process automation, and each application has its own unique requirements. That is a great idea, but doesn't that require a leap in hardware and software? I have seen many attempts to simplify the development and programming end, most using graphic-interface/no-programming-required ideas. The "programmer" pulls down the icon of the function he or she wants, opens the icon to add the I/O or other needed info and links icons in the flow pattern.
"But these all proved ineffective, and one size does not fit all applications. Plus, inexperienced people may not realize the many ‘little details' to consider that experienced controls people automatically design in—the reaction time of a solenoid, for example, or how long a cylinder rod takes to move, hydraulics vs. pneumatics vs. electricity for movement.
"And the mechanical side has to be considered as well as the electrical/software parts. Once a controller is successfully programmed and running properly, much of the future care [is in] the external and mechanical areas—the external sensors going bad, mechanical wear, welding tips on robot arms.
"So if someone has improved on the ‘usual methods' of controls design, what is the cost difference? I for one would like to see this kind of thing."
Timothy Clark, director of automation services at Stellar Automation Services responds: "While I agree with everything that John says, I think much of this starts with integrated approaches to software and hardware development. You simply have to look at the mess of communications in process applications to see there are a lot of hurdles to easier implementation. The biggest issues, it seems to me, are the embedded automation and the drive to have things look ‘open' and yet still be proprietary. For example, there is still a hardware-specific programming software package for each PLC, DCS, BMS, etc."
Selvan Murugan, lead A&I engineer at Stewart Scott International says: "This [ease of implementation, operation and maintenance] is a very important criterion when you're working in countries where the technical education and skills level are low. This needs to be considered if the business objectives are to be met."
Ron Hunter, a process control engineer at Invista says: "It is easy NOW. You should have been doing this work 25 years ago. At that time it wasn't easy..."
Christy Thomas of Equate Petrochemical Co., Kuwait, says: "PA technology has become easy and simple to implement and maintain by going in for open system (Windows-based) platforms and networking. However, the area PA needs to focus on improvingis the IT skills of PA engineers. PA engineers can no longer run away from IT networking skills, Windows operating system skills, switches, routers, etc. Industrial IT must become an invariable component to any future PA technology."
Dave Parks, engineering specialist at Mangan Inc., weighs in: "If we make it too easy, then anyone could do it, and then we would be out of a job. "
Mauricio Santos, automation consultant at Braskem, counters: "I don't agree that it's easy. It encompasses a lot of different and very specialized disciplines. In order to make the question and the answers clear, I would suggest making a more comprehensive survey listing PA technologies. I think this would be very interesting and helpful.
Luc De Wilde, DCS/APC/OPT specialist at Total Petrochemicals, contends: "I had my first DCS training course in 1985. It was a two-week training on TDC2000. With this training I was ‘fully' trained. Today, you need several months of training before you master all functionalities of the systems. Today, we have many more tools on the DCS. It is more user-friendly, but it's simply ‘bigger' and more complicated. So, yes, it has become easier. No, it has become more complicated."
Phil Sallaway, new business development at PUP Co., wrote: "Yes, it should be, but engineers take pride in designing a complicated piece of equipment, [the kind in which] if you adjust A, then calibrate B, while tuning Z, and have special tools X, Y and Z, it is no problem to get it working—after you get J,K L, M, N, O and P properly aligned. Sorry, but I'm a product manager who had to fight this fight. Keep it simple. Plug-and-play works. Make the sensor talk to the controller and say, ‘Here I am. This is what I am. And, ta da! Let's talk.' "
Paul Nelson, senior engineering specialist at Dow Corning writes: "Yes, systems should be easy to use. But, I don't agree that products are complicated because engineers take pride in complicated systems. Most engineers agree with Einstein: ‘Make everything as simple as possible, but not simpler.'
"PA products are not designed by people who use them. They are designed by software or systems specialists trying to fulfill a list of product features generated by a sales or marketing research team. It is a fact of life that marketing and sales folks like widgets designed into products, even when the value of these widgets is questionable.
"Beware of comparing PC technology (plug-and-play) to automation systems. Standards that make systems easy to assemble from disparate vendors are generally not appreciated by large automation system vendors, because it weakens their monopoly. Easy-to-configure and standards are things that end users and smaller disruptive companies support. If we want simpler, easier-to-use systems, we will have to demand them from our suppliers."
Mahzad Pakzad responded: "Here's what makes it difficult to design a simple system that satisfies all. 1. The design, development and marketing need to make sure the product will sell well to pay back the investment. 2. Our companies, in general, have not value-stream-mapped their processes and have bugs and issues within their own processes. 3. Company to company, the characteristics of operations vary in so many ways, including the capability of the end user to understand and use a new product. 4. We buy these systems to help us improve our operations, but never take time with all end users to review the compatibility of the system with what each group and the company as whole needs, or try to see what really is a good solution and practical to use as a standard.
"Usually individuals have to struggle to apply what they learn in group training (if any) to their specific task and application that may very well be quite different from the one being used by the guy sitting next to them. I always worry about the effects that standardization could have on making products a good fit for each and every application."
Gary Stortz, sales manager at Chartwell Electronics, concludes, "These were always important criteria. The fuzzy one is the price and it's one thing that does move up or down in the list of ranked criteria."