HART 7: Do we have wireless war after all?
September 5, 2007
This Friday, Sept. 7, the HART Communication Foundation board plans to vote on the HART 7.0 specification, which includes the wireless specification known as WirelessHART. Honeywell, a board member of HCF, intends to vote no on this particular issue. I want to take this opportunity to share our position, as well as invite your readers to join Honeywell in urging HCF to agree to consider adopting the ISA100 standard - a single, unified standard designed to facilitate communication for all fieldbus protocols, not just one.
Honeywell is concerned the industry is heading down a path that creates confusion and slows innovation through the adoption of two industrial wireless protocols. The industry is inevitably comparing the recently affirmed ISA100 Principles of Operation with the proposed WirelessHART specifications. The most striking difference is that while WirelessHART is designed to support the HART protocol only, the ISA100 standard is designed to support multiple protocols, including HART.ISA100 is positioned and designed as a universal network, transporting information from all types of industrial wireless protocols. Backed by ISA's standard-setting expertise, heritage, and knowledgeable end-user members, ISA100 supports implementation of protocols such as HART, Profibus, CIP and FOUNDATION Fieldbus on top of its flexible application layer.
This obviates the need for single protocol networks like WirelessHART. ISA100 accomplishes this in an efficient, secure and high-performance manner.
Functionally, WirelessHART and ISA100 are like a pager and a cell phone, respectively. A pager is a single purpose device dedicated to one function, like WirelessHART is dedicated only to the HART protocol. However, a cell phone is a more universal device designed to efficiently and effectively perform many functions while also providing the paging function. Users are understandably wondering why they would ever need the subset (WirelessHART) if they can have the superset (ISA100).
During the ISA committee's July meeting, it approved the Principles of Operation, setting the stage for the ISA100 draft standard to be released in October. Neither standards group has yet to propose or approve test and certification requirements, but both groups plan to have this final step completed in early 2008. It simply makes no sense to pursue WirelessHART when ISA100 will be available in a similar timeframe.
Honeywell has always been, and will continue to be, a strong supporter of the HART protocol. Honeywell believes the best path for HCF's continued success is to remove WirelessHART from HART 7.0, adopt ISA100 as the networking technology for HART wireless deployments and adopt the remaining portion of the HART 7.0 specification.
We invite your readers to join us in urging HCF and its board members to implement wireless deployments on top of the ISA100 application layer, as other fieldbus protocol organizations are planning to do. It is in the best interest of the industry to rally around a single, universal wireless network that supports a variety of protocols and has the ability to be flexible in the future. Wireless will revolutionize in-plant industrial communications, and we hope you will join Honeywell in urging the HCF to lead the industry in the right direction.
Honeywell Process Solutions