development of PackAL. “The organization of machine communication and commonly used functions facilitates seamless machine programming across control platforms and between machines from different vendors. The benefits are considerable for both machine builders and end-users. They are freed from unnecessary programming efforts, and more of their valuable time can become available for process-specific solutions.”

“With standard programming, companies don’t have to retrain their people for various machines, which helps lower their overall business costs.”

It’s not hard to see how these various standards fit together. “Convergence” is the term some in the standards community are using to describe the way that the different standards are beginning to fit together like pieces of a jigsaw puzzle, the intended picture being one of greater openness and reduced cost for OEMs and end-users alike. So far, however, the action has largely focused on improvements at the plant-floor level. That’s beginning to change, though, and the vehicle for that change is ISA-95.

The ISA-95 standard for Enterprise-Control System Integration was released in 2000, with additions published subsequently. It aims to facilitate the flow of data from the plant floor up through the MES space to the business, or enterprise resource planning (ERP), level. It does this in part by providing a lexicon of standard terminology so that the different levels can communicate unambiguously, and in part by providing a series of interfaces so that the different functional levels can, essentially, plug into each other.

GOING DEEP

In response to competitive pressures, management is striving to get data from deeper within the plant floor,” notes John Wenzler, food and packaging key account manager for Bosch Rexroth Corp., Electric Drives and Controls Div., a Hoffman Estates, Ill.-based vendor. “The information they need is available on the plant floor, but the challenge is to make sure they can get it in a timely manner. ISA-95 provides the handshake between ERP and factory floor systems, allowing that to happen.” In addition, Wenzler adds, because ISA-95-based interfaces are open, they keep users from being locked into a single vendor.

Allowing something to happen and actually having it happen are, of course, two different things. That was the case with ISA-95. After being promulgated at the dawn of the millennium, it languished, employed in a relative handful of applications. (Indeed, as one source remarked, you could almost hear engineers muttering, “What, another standard?”).

That began to change in 2004 when the German software giant SAP AG adopted it, and the legion of software companies that work with SAP began to incorporate it into their offerings. Now, to use a decidedly non-technical description, ISA-95 is progressing like a snowball rolling down hill.

Shawn Nelson, a sales engineer with Motion Tech Automation, a packaging machine distributor in Oakdale, Minn., is beginning to see the benefits of standards implementation in many packaging facilities he calls on. He cites the case of the IEC languages. “In our market locally, people are starting to recognize the value in having standard programming languages so that when they use products from different vendors, they don’t always have to reprogram. It’s like choosing a new brand of PC (personal computer) and knowing that [the Microsoft] Windows [operating system] is still going to run on it. And, if they’re more comfortable with programming in ladder logic, that’s still available to them, they’re just not locked into it.”

PEOPLE SIDE

Then there’s the people side of standards. “With standard programming, companies don’t have to retrain their people for various machines, which helps lower their overall business costs,” says Nelson. In today’s business climate, notes Bosch Rexroth’s Wenzler, that is more important than ever. “Because of the downsizing of engineering staff—both at the end-users and the OEMs—it’s critical that new people come up to speed quickly. Standards, and IEC 61131 in particular, help them come up to speed.”

“Still,” cautions Nelson, “in order for standards to really take hold, the vendors have to fully commit to open connectivity. If there is a standard but the hardware doesn’t comply with it, then what good is it?”

For more information, search keywords “IEC 61131,” “ISA-88,” “PackML” and “ISA-95” at www.automationworld.com.