Wireless use in the process industries has changed enormously, says Jeff Becker, director of the global wireless business, Honeywell Process Solutions, Phoenix. “About a year ago, we saw clients move toward holistic wireless networks,” he recalls. To him, that indicates scalability using wireless networks has become more critical plantwide.
Last year, all the talk was about wireless instrumentation, which, of course, is an important aspect of wireless, says Hesh Kagan, managing consultant in the enterprise architecture and integration group of Invensys Process Systems, Plano, Texas. “This year, we’re seeing our customers readily embracing enterprise-wide wireless solutions such as mobile operator, asset tracking, maintenance management, video and VoIP [voice over Internet protocol] telephony.”
Industry’s made huge progress, agrees Bob Karschnia, vice president for wireless at Rosemount, Chanhassen, Minn., a unit of Emerson Process Management. “Industry has used niche applications such as level gauges for 20 to 30 years. But over the last year, use of wireless has started to move into the mainstream.” It’s like an epiphany, he says. “All of a sudden, end-users are saying, ‘I get it.’ And then they see multiple applications through wireless as potentials.”
That hasn’t yet translated into a lot of action yet, though, because there’s still some uneasiness about relying on the technology, notes Robert J. Schosker, product manager for intrinsic safety, HART, signal conditioners and surge in the Process Automation Division of Pepperl+Fuchs (P+F), Twinsburg, Ohio. “It’s a trust factor about wireless,” he explains. “Some of the biggest obstacles are mindsets. Even though the technology has been around for a long time, people are still nervous about it.” But he counsels: “Wireless is a great way to go. It is the future of process automation.”
A Change in Attitude
The biggest advance in the last year or so isn’t in technology but in end-user attitude, says Kagan, past president of the Wireless Industrial Networking Alliance, Research Triangle Park, N.C. “There is a much greater understanding and appreciation of the fact that when engineered and used correctly, wireless really does work and is secure.”
But construction and deployment can pose significant challenges. “These radios must be correctly specified for the environment they’re to be placed in. That includes correct physical placement, as well as mounting and cabling of radios and antennae,” Kagan says. The interface to the wired network is another area requiring attention, he notes. “This, too, must be handled with careful engineering and full local IT (information technology) support.”
One lingering obstacle is battery life for self-powered remotely placed wireless devices. “Nothing’s changed. The technology is improving all the time,” notes Gareth Johnston, wireless product manager with ABB Ltd., St. Neotts, U.K. “[But] some devices will [have to] be externally powered.”
Energy harvesting may provide a viable option in some cases. Solar panels are well-established but recovering energy from other sources such as equipment vibration or thermal gradients is progressing. For instance, GE Energy, Minden, Nev., at the recent ISA Expo in Houston, introduced a wireless condition monitoring system with an optional unit that scavenges energy from vibration (Figure 1).