Ethernet still reigns in industrial control

摘要

The world of industrial control still appears to be a wired Ethernet environment, and it likely will stay that way for the foreseeable future. The industrial-control sector possesses a unique character and carries certain nuances that sometimes preclude the early adoption of cutting-edge technology. For example, industrial-control products, have a much longer design cycle than those in other market segments. In the consumer electronics and personal computer industries, where everything changes every six months, the design cycle is quite abbreviated. In the industrial-control sector, however, decision makers are conditioned to think in terms of decades. In fact, some companies are still using 8088 microprocessors running DOS―first used in the 1970s. In addition to design cycle problems, performance is another critical issue. How one defines performance depends primarily on the type of manufacturing being done. For instance, engineers have divergent opinions on what "real-time" means. In one sector of manufacturing, an engineer might tell you "hard realtime" means getting information in one-minute cycles, guaranteed. In a different sector, an engineer may tell you it has to be within 10 microseconds or faster. In one area of manufacturing, missing your "real-time window" might simply mean you have to wait through another manufacturing cycle. In a different sector, missing the window could mean the whole system crashes.