Throughout my career I have worn several hats (Engineering, Maintenance, and Production) and have gained different perspectives on what makes automation projects successful. One of the most important facets of any automation system is the controls package purchased for the system. Often, there is a cloud of mystery surrounding controls. What most people know is it involves electronics, programming, and smart guys sitting behind a laptop. With this article, I hope to take some of the mystery out of the decision process and break down what to look for and what questions to ask when you are about to do business with a controls integrator.
What’s matters most….
This industry “buzz word” simply means that the control system is put together using commercially, off-the-shelf components and software. You must understand what building blocks are being used in the design of your controls system. Verify that the controls integrator is using commercial components. Be careful not to let them slip in a “home grown” control system. You should demand that commercial PLCs (such as Allen Bradley or Siemens) be used with their native programming language. If your desire is to have PC-based controls insist that a commercial PC industrial controls language (such as Steeplechase) is used. If you fall into the trap of buying a “home grown” control system you are looking at years of expensive support, frustration about lack of upgrades, and a general feeling that you are being held hostage. If you are being sold on custom controls say “thanks, but no thanks” and run the other direction.
The day will certainly come when the people who designed the control system are not at your site, and you have to troubleshoot a problem. This is the time when you will truly discover if maintainability was designed into your system. The two biggest components of maintainability are documentation and the ease of following the program. Make sure you get “as-built” drawings of your control system and make sure you understand how to read them. A good controls integrator will spend time with key people at the customer site making sure they are comfortable looking at the prints. Also, is the code written in such a way that you need to have a Masters Degree in Computer Science to comprehend what is going on, or is it written with the understanding that electricians and manufacturing engineers will have to be able to follow along? Also, does the controls integrator have excellent comments in their program or are comments an afterthought? Be prepared for the day that you may be left flying solo.
Design with Spare Parts in Mind
A controls integrator with a grasp of how a factory or distribution center works will work hard to minimize the number of parts in your system. For example, in a lab environment, for optimal performance, six different photo eyes should be used. In the real world, though, a single photo eye can be used and reduce required spares and increase the likelihood that a spare is available when it is really needed. Try to find a controls integrator that has experience in the “real world” and who puts a high value on maintainability.
24/7 Support Availability
Even when a controls integrator is careful to make a controls system maintainable the inevitable time will come when help is needed. This is the crucial time. Do you have to dig up a phone number tucked in a drawer somewhere for the number of the guy you think worked on the system once? Or is there a prominent sticker on the panel with a toll free number you can call at any time to get expert support? I can tell you from experience the latter is a much better situation than the former. Endless hours of frustration can be avoided if you had the opportunity to get help from an expert. Make sure that the technical support being promised by your potential controls integrator is truly 24/7 and not just the number of some guy who may or may not return your call in a timely manner.
Best of luck in your search for a controls integrator on your next project. If you keep these foundational things in mind, you will be on your way to a successful project. Feel free to contact me if you would like a little help navigating your way through this decision. I am always happy to help.