By presenting CPS at its user conference, ARC appeared to be endorsing GE Fanucs approach, an endorsement which GE wasnt slow to exploit. We share the vision for breaking down the barriers associated with the traditional layered production environment with thought leaders such as ARC, said Control Systems vice president Bill Estep. The CPS model and our solutions are closely aligned to deliver value to manufacturers globally. Dissolving the walls and eliminating boundaries that our customers have faced between Operations Management and Automation Systems is exactly what we have been focusing on with our solutions, and the ARC CPS model clearly articulates the next generation model for those seeking operational excellence.
Whether any of that increases the chances of us all stopping talking about MES and latching on to CPS as the new must-have acronym remains to be seen, but previous experience is not encouraging. After all its the very vagueness of MES which makes it so useful to vendors, allowing them to claim it or deny it as expediency dictates.
Does gateway commit ISA to a WirelessHART future?
ISA and the HART Communications Foundation (HCF) seem to be making up for lost time in their attempts to achieve a single wireless standard. Following their initial decision to collaborate on seeking ways to incorporate the newly released WirelessHART protocol into the ISA 100 Wireless Systems for Automation standard, they held a series of meetings at last months ISA Expo event in Houston, which appears to have charted a possible way forward.
That initial decision to collaborate was prompted, at least in part, by Honeywell Process Solutions president Jack Bolicks last-minute attempt to hold up release of the HART 7 protocol on the grounds that it would lead to the emergence of duplicate standards and hence confusion among users.
It looks very much as if similarly strongly expressed views from other leading vendors have been responsible for maintaining the momentum. For example, ABB Instrumentation technology vice president Sean Keeping wanted to avoid a costly repeat of the fieldbus saga which has led to ABB having to incorporate support for Profibus, Foundation fieldbus and HART into its field devices, tools and host systems. This duplicated design effort has been costly for ABB and other suppliers, and has made life confusing for users. We would strongly advocate avoidance of a multiple standard path for wireless sensor communication, he said, to which end . . . ABBs recommendation is that SP100 incorporate the WirelessHART specification as its solution at the instrument level for PV Monitoring, Asset Performance Management and eventually control.
His view was echoed by Siemens Sensors and Communication divisional president Hans-Georg Kumpfmüller when he said that recent events showed that it is the wish of the industry to get more harmonized solutions, bridging the different standards existing on the market.
Emerson chief strategic officer Peter Zornio and Endress+Hauser corporate director for Projects and Solutions Frank Hils added their voices in support, with all four companies indicating their intention of having WirelessHART-compliant products available during 2008.
According to ISA, the outcome of the Houston meetings was that the ISA 100 committee would attempt to accommodate the HART 7 wireless protocol in release 1 of the ISA100.11a standard through a dual-gateway architecture, followed by a potentially more integrated approach in release 2. ISA100 co-chair Wayne Manges of Oak Ridge National Laboratory said that the approach had the support of end users, suppliers, HCF representatives and the ISA100 members on the evaluation committee, who all saw it as the most viable alternative to address the needs of the end-user community, both in the short and long term, while his fellow co-chair, Pat Schweitzer of Exxon Mobil, explained that the joint Analysis Team was evaluating how
WirelessHART could be incorporated into the ISA100.11a standard without compromising the original ISA100 objectives. The most important part of that evaluation is the obligation to continue our commitment to the end user, and were confident that our final decisions will accomplish that goal, he said.
To that end the committee is to consider a number of options including dual-stack end devices for integration at the device level, tunnelling with pack at the device level and unpack at a higher level and future integration at the MAC, DLL and NET/TRAN levels.
All of which seems to be slightly at variance with the view expressed by Honeywell global wireless director Jeff Becker, who was reported as saying that Honeywells understanding was that the committee had agreed on a dual-network, single-gateway compromise in Release 1, moving to complete interchangeability and a single network in Release 2.
The difference may be more than just one of semantics. A Release 2 which embodied a single network which was not WirelessHART or at least WirelessHART-compatible would potentially leave stranded users who had invested in WirelessHART devices in the interim, which could be three years or more while, on the other hand, confirmation of WirelessHART as the only protocol for field device communication would appear to leave Honeywells own solution out in the cold.
Actual ratification of Release 1 of ISA 100 is not expected before the end of 2008 which makes it unlikely that compliant products will be available before mid 2009. That would appear to give vendors of WirelessHART products a clear 18-month plus window in which to establish WirelessHART as the de facto standard, with the added validation of their being compliant with ISA 100 Release 1 thereafter. Given that a further year or more will have elapsed by the time Release 2 is complete, its difficult to see how ISA could contemplate a situation in which a significant installed base of compliant devices are effectively rendered non-compliant by a further release of the same standard. In effect, by conceding the case in Release 1, ISA100 seems to be committing itself to adapting its architecture to accommodate WirelessHART indefinitely.