Chemical Processing - September 2007 - (Page 55)

in a harsh environment on which the devices will have to operate in, but in a wire-free economy,” Weiss explains. WirelessHART also includes several features that are essential for wireless of any type to take hold, adds Robert Shear, Dust Networks’ director of market development. Those include channel hopping, self-organizing mesh and time synchronization. The latter unlocks the economics for the new specification, he says. “You end up with the ability to have battery-powered routers allowing frequency hopping.” “The fact that there are batteries contributes to the low initial cost,” explains Weiss. “The highest cost element [in wired automation systems]: It’s still cable and conduit and the time associated [with installation] and the disruption associated with a plant [through that installation].” Potential users certainly will value two attributes highly, notes Martin Zielinski, director of HART and Fieldbus Technology for Emerson Process Management, Austin, Texas — reliability and coexistence, or the capacity of the wireless bands to carry traffic from various transmitters. Immediate value Many plants in the huge installed base of control systems using wired HART’s 4–20-mA loop lack the economic justification or technical capability to access HART devices’ intelligent information. WirelessHART will significantly change that, Helson predicts. “We tried to make it as easy as 4–20 mA, by extending the protocol with a view to allowing use of similar tools: selfbuilding, self-healing networks and minimal engineer input,” www.chemicalprocessing.com explains Gareth Johnston, fieldbus-communications specialist with ABB, St. Neotts, U.K., who helped develop it. End-users who understand the benefits of asset management will embrace WirelessHART, believes Dave Smith, manager, plant-network-technology systems marketing for Yokogawa of America, Newnan, Ga. It’s a “solution adding digital communication for device configuration and/or various prognostic/diagnostic functions provided by intelligent field devices — with minimum or no changes to control configuration.” “It fits well with maintenance and asset management strategies,” adds his colleague Nobuaki Konishi, senior general manager of IA Marketing Division, Yokogawa Electric, Tokyo. He foresees a definite role for the new protocol for monitoring and alarming. Two early asset-management applications come to mind to Siemens’ Stephan. One is transport of field-device diagnostic data. That’s because in the installed base, “precious diagnostic data. . . is lost in about 20 million devices, or must be read manually due to a lack of HART functionality in the remote I/Os (inputs/outputs),” he notes. The other: “complete wireless integration of process values and diagnostic data of field devices.” Zielinski also expects WirelessHART to excel for bringing in now-stranded diagnostic information. “Of the millions of installed devices, about 2 million digitally communicate,” he estimates. “For the rest, WirelessHART provides an add-on to communicate digital information back to the asset management system.” Up until now, with the 4–20-mA loop and September 2007 • 55 http://www.chemicalprocessing.com

Table of Contents Feed for the Digital Edition of Chemical Processing - September 2007

Contents From the Editor Field Notes In Process Energy Saver Compliance Advisor Succeed at Simulation Rethink Your Approach to Process Safety Avoid Blending Blunders Get the Right Cartridge or Bag Filter Wireless Proponents Take HART Membrane Boasts Material Benefits Process Puzzler Plant InSites Chem Show Product Preview ISA Product Preview Equipment & Services Product Spotlight/Classifieds Ad Index End Point

Chemical Processing - September 2007

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