Who’s Using Wireless Now?
You are, that’s who. Our survey (see the sidebar “Survey Snapshots Wireless Users”) shows that over 50% of you use WiFi in the plant, while 40% use proprietary wireless networks and 24% use RFID in your plants.
What seems to be happening is a sort of “guerrilla wireless.” Maintenance organizations are working with wireless tablet PCs, such as we described in our article “Wireless While We Work” in the Aug. ’06 issue . Cell phones and web-enabled PDAs are running applications like Transpara’s Visual KPI. 802.11b, g and n nodes abound around the plant environment, in control rooms, marshalling rooms, and other sometimes unlikely locations.
Wireless Asset Management and Process Optimization
Although the wireless survey shows that only about 24% of users are interested in using wireless for maintenance systems, the big noise from suppliers and involved end users about the proposed use of wireless sensors has been asset management. Temperature, vibration, and pressure monitoring of rotating machinery has been touted repeatedly as a primary wireless sensor application, especially if low-power, low-cost, wireless-enabled sensors are common. The HART Communication Foundation’s Ron Helson says just the ability to extract the diagnostic data from all the existing installed HART-enabled field transmitters and control valves would enable improved asset management, with concomitant savings. He notes that of the 22 million-plus installed HART-enabled devices, less than 10% currently extract their diagnostics in real time.
Other wireless pundits point out the advantages to process optimization using wireless sensors. The reason we originally used single-loop control was that it was easier and less expensive to do, especially with pneumatic control loops. Wireless and inexpensive sensors will change that. The mathematics is clear on this point: multiple casual measurements of multiple parameters can provide more robust and more precise measurement overall than a single highly accurate point measurement can.
“This may be the next inflection point,” says Dave Kaufman, Honeywell’s director of business development. “The development of ‘lick and stick’ sensors is coming rapidly, and will make those casual measurements possible and practical.”
The Standards Landscape
The standards landscape is still littered with overlapping standards, methodologies and interest groups.
Vendors can and do take advantage of this to sow FUD. When asked about the future of proprietary wireless networks, such as his own, Sensicast Systems’ CEO Gary Ambrosino says, “The wireless ‘standards war’ taking place in industry today is far from over!”
Yet our survey shows that more than 70% of end users want one standard or one network for many applications.
Ambrosino continued, “Driven by technology capabilities, vendor traction and market politics, the wireless industry and ongoing developments in standards bodies will continue to be in flux. Sensicast believes ‘proprietary’ radio systems will continue to thrive, and be deployed for as long as they can drive compelling wireless applications and provide business value to those who deploy them.”
Ambrosino may not be wrong. According to Yu-Gene Chen, Honeywell’s business unit manager for wireless, Honeywell’s own surveys indicate that its primary customers in the petrochemical industry are willing to continue using proprietary networks until at least such time as SP100 announces a standard.
If SP100 is delayed in development, proprietary networks may have enough time to develop a strong foothold, and they may never be dislodged by an “official” standard.
The good news is that standards development is moving forward. In June, the members of the HART Communication Foundation voted to approve the HART 7 Specification, and with it the standard for WirelessHART. While compliance testing methodologies have yet to be worked out, more than 10 companies, including Emerson Process Management, Yokogawa, Elpro −now part of MTL, ABB, and others will have WirelessHART devices, both for connection to existing HART devices, and new, WirelessHART-enabled field devices, for sale by the end of 2007 or early 2008.
Plans for this have been going on for nearly two years now, as you can see by listening to a podcast interview with Elpro’s CEO, Graham Moss, recorded in 2005. “We’ll have a device out within six months after the specification (WirelessHART) is approved,” Moss said.
In May, Helson and Wally Pratt, HART’s chief engineer, made a formal presentation to the SP100 committee to describe the then-proposed system, which has since been adopted as the standard. You can see their presentation on ControlGlobal.com by going to www.controlglobal.com/articles/2007/184.html.
All the Different Ways to Wireless
Many standards can mean tough decisions for process control engineers.