Wireless Standards

Those involved with the standard called ISA100 Wireless Systems for Automation seek one wireless structure for industrial use, incorporating multiple protocols used for industrial communications. End-users, automation vendors, original equipment manufacturers, system integrators, and others are creating an umbrella approach, seeking shelter from a deluge of wired industrial protocols.

By Mark T. Hoske, Control Engineering July 30, 2009

ISA100 family of wireless standards is being designed to meet plant-wide needs today and in the future by accommodating all plant processes with one series of standards, ISA says.

Those involved with the standard called ISA100 Wireless Systems for Automation seek one wireless structure for industrial use, incorporating multiple protocols used for industrial communications. End-users, wireless automation vendors , original equipment manufacturers, system integrators, and others are creating an umbrella approach, seeking shelter from a deluge of industrial protocols for wired industrial applications. Fresh with knowledge from the ISA100 committee meeting in Kyoto, Japan, three participants explain how the standard is organized, how it’s progressing, and how it’s evolving within ISA faster than any standards effort to date.

ISA100 has tried to get more people involved and to move things along more quickly, suggests Larry Pereira, co-chair of the Marketing Working Group for ISA100 Committee. Pereira is also head of FlexWorks Solutions Int’l Consulting. Efforts seem to be working. ISA100 participation includes 600 members representing more than 200 companies, with more than 65 voting members.

The first wireless standard within ISA100—ISA100.11a Process Automation Applications Wireless Standard—was completed in December 2008 and moved faster than any other ISA standard, says Wayne W. Manges, one of two co-chairs for the full ISA100 committee, and also Oak Ridge National Lab program manager. Two ISA100 technical reports also have been produced since ISA100 work began in 2005.

Familiar conventions

Familiar conventions of the standard-making process remain, however. For instance, ISA100 has progressed through the ISA standard lifecycle: beginning with an interest group, advancing to a study group, and evolving into a workgroup. Along the way, members define mission and scope. They may produce an informative technical report (TR), a recommended practice (RP), or an appendix to a standard. If the workgroup produces a standards document, that language is normative, meaning “you shall do this.” The workgroup drafts, revises, and agrees to the language. Then all voting members do the same, with public review and additional revisions along the way.

“We started ISA100 with a request for proposals, where any company could submit,” Manges says, and some chose not to, citing intellectual property concerns. “ISA100 uses an ISO 7 layer communications, and we explicitly explained that we could not guarantee that the standard would allow a company to maintain full ownership of all seven layers. We’ve chosen best in class from each layer, and have taken a lot of heat from some vendors as a result,” Manges says. (He began his wireless involvement after a DOE industrial technologies program nine years ago linked system accuracy and efficiency to the number of sensors implemented. Wireless implementation can cost-effectively add sensors, he points out.)

Because ISA is well branded in the industrial space, it’s easier to overcome competitive perceptions, Pereira says. “Users are beginning to realize that this standard is open because anyone can join, participate and contribute at any time with no barriers to entry, and they can mix and match to fit their needs. It’s a higher form of collaborative process.

The standards process involves consensus, which at time feels like herding cats, says Patrick D. Schweitzer, the other co-chair for the ISA100 full committee, and lead instrumentation engineer at ExxonMobil Research and Engineering. As the National Institute of Standards and Technology (NIST) has stated in its workshops on Smartgrid, consortia can develop specifications faster, but participation is pay to play. “Within ISA,” he says, “we can get the best of the best to contribute. It may take a little longer, but we’re guaranteed a stable document.”

In a January committee meeting, Schweitzer said ExxonMobil participates in ISA100 development work because “reliance on proprietary or consortia-based specifications where we have no input or influence is a risk to future security, and to our commitment to excel and increase our margins. We feel this is the best option for us to continue to have freedom to operate and improve our operations.”

ISA100 group details

ISA100 participation is broken into more than a dozen working groups (WGs) separated into topics and designated by number. Groups from which a normative document could result also get a number based on the ISA100.xx naming convention. Here is a partial list of groups and what they’re doing.

WG1: ISA100.1, Integration. Ties the standard together and facilitates formation of new workgroups. It produced a technical report designed to help instrument technicians called “ISA-TR100.00.01-2006 – The Automation Engineer’s Guide to Wireless Technology Part 1: The Physics of Radio, a Tutorial.”

WG2: Technical RFP Evaluation Criteria (TREC), the “I just want it to work” group, charters the user community to develop wireless requirements. Since ISA100.11a has embraced all stated requirements to date, this group is not active (nor required to be) at this point, Manges says.

WG3: ISA100.11a, Wireless for Process Monitoring. “The user community had been asking for wireless sensor technology in an industrial environment for sensors with 100 millisecond latency or longer, focusing on noncritical or risk acceptable applications,” explains Schweitzer.

First draft garnered some 2,500 comments, leading to considerable editing to improve readability. Draft 2 passed and was balloted for ANSI public review; comments closed May 25. First time around, votes were shy of two-thirds approval; 81% (23 of 24 users) approved the second version. The final is expected to goes to the ANSI standard and practices board in July 2009, Schweitzer says. Development doesn’t wait, however. As with WirelessHART, companies have been developing to the standard before it is final. Some member companies have produced products and prototypes to ISA100.11a that they say are compliant or will be after minor changes to firmware, Schweitzer says. Also, the Chinese Institute of Technology is building devices to test the standard, he adds.

WG8: Users requirements, including battery life, will be addressed.

WG12: ISA100.12, WirelessHART Convergence. Members have been meeting for over a year to examine how ISA100.11a and WirelessHART can work together. Latest thinking looks at dual boot devices, where dual stacks implement at the same time. This allows HART to keep its intellectual property, Schweitzer says, while making users happy about interoperability. The group is working on an objective document comparing each, he adds. One difference is that WirelessHART requires routers; ISA100.11a doesn’t.

WG15: Wireless Backbone/Backhaul. Picks up the effort behind the gateway, substituting for wired Ethernet to the control room. “This is a whole different set of needs,” Manges says, including security, video, and ability to handle multiple protocols.

Capabilities of ISA100.11a provide support for multiple industrial protocols at the device and application.

WG16: Factory Automation. Will produce a normative standard for wireless factory automation, with tighter timing than ISA100.11a, among other differences. A requirements document is being drafted. Proctor & Gamble, auto makers, and other discrete automation participants are involved.

WG21: People and Asset Tracking and Identification. Covers RFID and other methods. This group also produced a related technical report.

Coexistence. Describes how two networks continue to operate in an environment where they don’t necessarily cooperate, Manges says, such as how ISA100.11a behaves in an environment where WiFi already exists. “In contrast, interoperability is the process for assuring the cooperating networks can effectively accomplish their shared function,” he says.

Commercialization: Outside the scope of the standard, certification groups will look at the options within the specification and work to certify interoperability among vendor devices, Manges says. One certification group, ISA100 Wireless Compliance Institute is developing a suite of tests.

ONLINE extra

See the following vendors’ views on industrial wireless and other wireless resources.

Wireless: Banner Engineering working with Nivis to offer ISA100, WirelessHART – Banner Engineering is evaluating a solution to support ISA100 and WirelessHART through a relationship with Nivis.

Wireless: Honeywell develops products to the ISA100.11a standard – ISA100 Wireless standard has various parts in development, focusing on varied industrial needs. Honeywell is developing products for the ISA100.11a standard, company says.

Wireless: Invensys, Wonderware look at OEM, end-user adoption – While customers of human-machine interface (HMI) software and process controls differ in their wireless understanding and abilities, users understand that wireless industrial applications will continue to expand, according to two experts within Invensys.

Wireless: Kepware can make up for less than stellar connection – Kepware protocols communicate over many infrastructures, wireless being one of them. Wireless communication is helped with a quality communications product.

Wireless security: Moxa offers WPA2 Personal and Enterprise – Among wireless options, Moxa Technologies currently supports WPA2 Personal and Enterprise, good for security, the company says.

Think Again: Wireless prosperity – Recent Motorola survey cites movement in wireless investments.

Wireless: Opto 22 supports global standards in products – Opto 22 says support for IEEE 802.11a, b, and g increases wireless design flexibility.

Wireless: Initial focus is WirelessHART, says P+F – Initial wireless focus for Pepperl+Fuchs is WirelessHART, though P+F also is open to ISA100.

See another Control Engineering article series: Industrial Wireless Implementation Guide .

NEW as of Oct. 7, 2009: ISA 100.11a wireless demonstration project in operation .

Author Information

Mark Hoske is editor in chief of Control Engineering. Reach him at MHoske@cfemedia.com .