I would like to offer my view on the topic of automation platforms, as seen from the trenches on both sides of the decision.
I worked for 20 years as a Journeyman electrician on shift in several different industries. Working on instrumentation and controls more than construction. I spent most of those years answering breakdown calls on production equipment. Currently I am involved in Sales Engineering with Advance Products, Inc., manufacturers of case and carton handling automation solutions. As a "salesman" I embrace the ability to offer an end user customer the controls equipment they specify. Yet working closely with the Designers, fabricators and programming staff at Advance Products, I see first hand the added expense of constantly changing platforms. It brings lost production time, added procurement costs, and increased labor costs, which are either passed along in equipment price (not good from the salesman's point of view) or absorbed by the equipment manufacturer.
Now from the old maintenance man's point of view, I worked 2nd and 3rd shift for a lot of those 20 years. I know how spotty outside tech support can be. Working in a medium to large facility, the shift electrician could see two or three PLC systems and a few other communication protocols in an eight hour shift. Production is down and you are looking for documentation, communication software and adapters, or 24-hr help lines to get things back up and running. I was expected to be familiar with several different versions of PLC software releases and various manufacturer's equipment as well as twenty different key combinations for other instruments and small controllers. Sure, there was training to help me in all of this, but as they say, "If you don't use it you lose it." On any given break down call you have supervision and production that have to wait while you pull out the book to work on something you haven't seen in six months.
Now back to today. While it is an inconvenience to our staff to use a platform that they are not intimately familiar with, we have the luxury of time—not a lot, but at least some—to work things out. The programmers are brought into the loop at the beginning of the design when non-standard controls are specified to help the designer understand any potential limitations or, in many cases, added features that may be involved. These programmers have the controls early on in the design phase to become familiar with and to work with the supplier, so that when it comes to operational trials the machine works as planed.
Yes it is a problem and an added cost, but it is much easier to work on these programming and communication issues in the work shop and not at 2:AM on the plant floor with product stacking up around you. In any equipment purchase there are two bottom lines, one the cost of new equipment and two the life cycle impact on operations from the new equipment. As a maintenance man I understood that if the equipment wasn't running it wasn't saving the company any money.