“OPC allowed us to focus on technologies in our wheelhouse instead of on custom code that likely would have been outsourced. We have DeltaV programming experts, and we have people that can write Oracle stored procedures. We do not have people that write custom .Net code to integrate various systems,” says Cox.
Pavilion Technologies and Rockwell Automation describe another integration project that took advantage of OPC and open standards. “We executed a control system/ERP integration project for a client that is truly a thought leader in the petrochemicals industry,” says Angel Sustaeta, the manager of strategic development at Pavilion. “The integration of the data from the business system was significantly enhanced by Rockwell’s acquisition of Incuity, and specifically by their use of open system standards such as OPC DA, OPC HDA and ISA95. These standards allowed us to implement the project in record time, even though the project had kicked off prior to the Incuity acquisition.”
Another leading automation vendor agrees that standards ease integration. “The biggest challenge when integrating hardware and software at the control and MES level from different vendors used to be getting access to the existing data,” notes Marc Leroux, the marketing manager for collaborative production manager at ABB. “But now most control vendors support OPC, which makes it easier to get to the data. At the MES level, almost everyone supports an ODBC database connection, and many new systems also support CML or web services. There is still engineering work to do, particularly in specifying the interfaces and getting agreement on the method used to access the data, but it is much easier to do now than it was five years ago.”
Leroux adds that standards such as ISA95 have done a good job of promoting integration between control systems and the enterprise. “The standard probably hasn’t decreased complexity, but it has eliminated a lot of risk for end users,” he says. “Now an end user knows that he can replace systems on either side of the interface with confidence that the interface work is not going to have to be redone.”
Non-Technical Challenges Remain
Although standards have eased the technical side of integration, non-technical hurdles remain high. The chief reason is that integration between control and ERP systems requires process automation pros to leave the comfort zone of their plants and enter new realms.
Justifying and implementing a change that affects only your in-plant automation system is relatively easy. You present your case to the plant manager, he or she accepts it, and you execute the project. You never have to leave the plant to justify and implement the project, and you only interface with familiar faces.
By contrast, control system/ERP links require interface with other departments, particularly the dreaded high priests of IT. “Interestingly, the most significant challenges are often not with equipment or systems, but with the personalities involved,” says Amy Davidson, product marketing manager for asset optimization at Emerson Process Management.
“Computerized maintenance management systems (CMMS) and other software suites are often owned by entities other than the maintenance departments that use them. In a project we implemented, CMMS was controlled by the IT Department, and IT personnel can be protective about others coming in and interfacing with their systems. At the same time, the IT staff seems to be removed from the plant personnel they were supposed to be serving. Once you get over the IT hurdle, the rest is easy,” Davidson adds.
Others also voice IT concerns. AOC Resins’ Cox says, “Engineering was responsible for getting data pushed to the Oracle ERP system. Where the data needed to go was defined, but getting the data to the spot reliably took an iterative process. A trial-and-error period was needed, but IT would not dedicate a resource to writing the stored procedures. Engineering had the capability to write the procedures, but was not allowed to, so progress was slowed due to territorial issues. Eventually the need for data overrode territorial complaints, and both parties focused on completing the development.”
Another non-technical challenge is simply finding the time to do the detail work necessary to perform integration, especially with the reduced staff on hand at many process plants. “Standards make database-to-database queries more convenient, but they still require manual initial associations to make the proper connections,” explains Jeff Waufle, IT technical services supervisor with Nevada’s Las Vegas Valley Water District.
“Linking databases requires knowledge of both systems. Staff members with this knowledge are usually people key to ongoing operations who have limited time to sort through the massive amounts of data that require accurate associations. It's not a complex problem, just one that requires tedious accuracy. Tasks can be distributed, but the more people involved, the more chances you have of inconsistent results,” adds Waufle.
In the past, best practices included lots of technical items, as this was where complexity was greatest. Now best practices are more focused on up-front justification and planning, because without justification there is no project. “For anything we do there has to be a return on the investment or some other reason to do it such as legal requirements,” says Gary Crenshaw, electrical engineer with Beam Global Spirits and Wine, Cleremont, Ky. “If there is no return on investment, there will be no integration from SAP to the plant floor.”