Discrete manufacturers may be feeling a bit neglected these days on the industrial wireless standards front.
The WirelessHart standard—developed primarily for use by process manufacturers—received final approval in September 2007, while the process-oriented ISA100.11a industrial wireless standard is moving toward expected final adoption later this year. Both have received significant coverage in the trade press. Meanwhile, a sister ISA100 standard to be aimed at discrete and hybrid manufacturers in the factory automation space is still only in the definition stage.
But that’s not to say that progress isn’t being made toward an industrial wireless standard for the factory automation arena. To get an update on the status of that work, Automation World spoke recently with Cliff Whitehead, co-chair of the Factory Automation Study Group for the Instrumentation, Systems and Automation Society’s ISA100 committee.
IEC collaboration
Among other things, Whitehead reported that the Group expects to move soon from a Study Group to full ISA Working Group status—the next step in its process. Further, the Group plans to collaborate with the International Electrotechnical Commission (IEC) for the development of an international factory automation wireless standard that Whitehead said could be ready perhaps within two years.
In defining the role of wireless in a discrete manufacturing setting, the ISA Group to date has focused on a couple of primary areas, said Whitehead, who is strategic marketing manager for Rockwell Automation Inc., the Milwaukee-based automation supplier.
One goal is to reduce maintenance costs through use of wireless technology for cable replacement in applications such as robotic arms, rotating tables and packaging machines, Whitehead said. Constant repetitive flexing can cause unexpected cable breaks and downtime, resulting in significant costs for manufacturers. These costs could be eliminated through the successful use of wireless communication.
The second focus area involves the need for low wireless latencies in factory machine applications. The wireless sensor networks to be used for monitoring temperatures, pressures and other parameters in the process industries can often tolerate latencies in the 100- to 500-millisecond range, said Whitehead. But discrete manufacturers need significantly lower latencies for many machine applications, he noted. “Ten milliseconds is the number that most people have cited as approaching acceptable.”
Documents coming
With the bulk of the ISA Group’s effort to date focused on determining “the boundaries of factory automation,” the next step is to develop very specific requirements around the scope that is emerging, Whitehead said. The Group plans to develop two informational documents, he noted. One will cover “Requirements for Wireless in Factory Automation,” and the second will lay out “Recommended Practices for the Deployment of Wireless Systems in Factory Automation.” Target completion date for these documents is next year’s second quarter.
When completed, these documents will be submitted to the IEC for its use in developing a factory automation wireless standard, Whitehead said, as part of “a fully collaborative effort between the two groups.”
Instrumentation, Systems and Automation Society
www.isa.org
