Plant to enterprise – Putting the pieces together

In addition, each side has its own firewalls and security procedures and proxy servers. “We keep it in pretty strict isolation,” says Valle. 

Culture Clash
Perhaps the harder nut to crack before we complete the journey is the cultural issue. While not everyone may feel as strongly as Hawkins that “Business people don’t think much of engineers because engineers want to do it right, and MBAs want to do it cheap,” the fact remains that there is a big language gap between the two. This gap is not only between the humans trying to arrive at a workable solution to their problems, but between the systems they’re using to do it.

ERP systems are about transactions and accounting. They use the old total-at-the-end-of-the-month paradigm. Plant-floor systems are about real-time monitoring and control. If the ERP systems aren’t designed to cope with real-time information, it’s also true that the plant-floor systems aren’t designed with financial databases in mind.   

“Control works with a physical model,” explains Dr. J. Patrick Kennedy, president and CEO of OSIsoft. “That’s a scalable model.” To add more capability, all that’s required is “more iron,” he says. “But most integration works off a product or process model. I don’t care about temperatures, but tons, volumes, etc. That can be fairly ambiguous, and [business] processes get changed all the time.”

At this failure-to-communicate level is where technology has finally caught up with the promise over the last few years to make integration easier. Software advances, such as extensible markup language (XML), simple object access protocol (SOAP), and, most pertinently, batch-to-manufacturing markup language (B2MML) have simplified writing the integration software necessary to make connections between plant and enterprise applications.

All of the major plant-floor system vendors—GE Fanuc, Emerson Process Management, Siemens, Invensys/Wonderware, Rockwell Automation, ABB—and even some smaller vendors like Citect (now owned by Schneider) and Iconics—have developed architectures to enable easier data transfer between various parts of the plant floor and between the plant floor and the enterprise. At the same time, ERP vendors are reaching out to make linking to the plant floor easier. 

Just last month, Invensys released two SAP-certified applications for process and packaged goods manufacturers that can be plugged into existing industrial automation systems to provide interoperability between them and SAP enterprise software.

SAP and ABB worked together to build the XML-based interface between its ERP and advanced planning and optimization (APO) applications and ABB’s manufacturing execution system (MES) at German papermaker Steinbeis Temming. Orders flow from the ERP system to MES for production optimization and control, and data about goods movement and order progress goes back to the ERP for dispatch and invoicing. The link “enables us to track every individual batch,” says Hans-Gerd Lachmann, Steinbeis Temming’s IT manager. 

Other major ERP vendors are also making overtures to the plant. Oracle has been one of the leading supporters of Open Applications Group Inc. (OAGi) since its inception, and has supported the Open Applications Group Interface Specification (OAGIS) scenarios and business object documents within its Oracle E-Business Suite. Microsoft’s .NET initiatives and its rebranded Dynamics line of ERP systems targeted at specific industries are also easing some of the connectivity challenges, especially for smaller operations. All of the big ERP vendors are also paying close attention, and in some cases, actively participating in developing the standards that are enabling integration success stories. 

Standards Issues
The ISA88 and ISA95 standards are important builders of the bridge across the plant-floor/enterprise divide. ISA88 deals with the control and process engineers’ view of batch processes. ISA95 looks at data on the next level of the stack: the operational views of interest to plant supervisors, production managers and operators.

“We’ve made good progress in connecting the MES layer to the enterprise,” says Keith Unger, principal manufacturing IT consultant for systems integrator Stone Technologies, and a member of the ISA88 and ISA95 committees. “We’ve done some excellent implementations through OPC. We defined equipment and how it needed to operate. ISA88 is bottom up and ISA95 is top down. We’re hoping to meet in the middle.”

In short, says Unger, the back office says, “Please produce these products using these materials,” and the plant responds, “This is what we actually produced.”  What ISA95 does is provide the common language to enable that communication to take place.

Of course, there’s still a long way to go. The standards themselves aren’t complete, and education is still a big issue.

At a recent tradeshow, Advanced Automation’s Michael asked attendees at a presentation how many of them were familiar with ISA88. “A lot of them couldn’t identify it. ISA88 and ISA95 are moving this forward, but it’s a challenge even when organizations are cooperating. How do you educate folks down in the plant? Clearly, if companies want to get broader adoption, they have to do more on education further down the food chain.”