Over the past three years, wireless field networking technology has taken the process industries by storm. Answering the need for fast and easy implementation relative to wired alternatives, hundreds of wireless mesh networks and thousands of wireless sensors have been successfully deployed and continue to reliably, efficiently and economically broaden the measurement landscape.
“The principal advantage we see around wireless is the ability to accumulate and analyze a much greater array of data than would otherwise be possible,” says Michael Ingraham, technical manager at BP’s Cherry Point refinery in the U.S. “Wireless enables us to get more data more efficiently, more economically than we ever have been able to in the past.” (For more ideas on how leading process manufacturers are innovating globally with wireless field networks, see the article, “Far From Quiet on the Wireless Front.”)
In addition to the new frontier of sensor data afforded by the wireless field is a large and rapidly growing class of wireless success stories: “plant-level” applications that are boosting the productivity, safety and security of plant personnel as well as easing the connection of physically disparate digital systems into an integrated whole.
To accommodate the disparate needs of wireless field- and plant-level applications, Emerson Process Management’s Smart Wireless architecture consists of two layers that are seamlessly integrated with the company’s control and plant network offerings (Figure 1). The plant-level wireless layer is based on Cisco’s Unified Wireless Network architecture, and is managed through the Cisco Wireless Control System (WCS) platform.
Ways to benefit from plant wireless
Having successfully implemented hundreds of wireless field network applications, Emerson has more recently seen a dramatic up-tick of interest in plant-level wireless network applications. Topping the list of customer requested wireless applications are: empowering mobile workers, location tracking, safety mustering, integration of non-traditional signals such as video, and bridging remote or isolated control systems.
Mobile worker productivity. Perhaps most appealing of all wireless plant network applications are those designed to enhance the productivity of mobile workers. Indeed, it’s here where perhaps the biggest wireless plant network returns are to be made—incremental productivity improvements that pay off repeatedly. “The dollars really add up when you can save 10 minutes to an hour, over and over again,” explains Neil Peterson, wireless services marketing manager for Emerson Process Management.
The variety of wireless-enabled mobile devices now available ranges from hardened, 13-in. tablet PCs to ½-VGA palm-sized devices to hand-held communicators. For example, the Panasonic U1 is a handheld PC that includes built-in Wi-Fi and cellular communication capabilities and is able to run a full-featured Emerson DeltaV operator interface client.
“The operator is no longer chained to his desk,” Peterson says. “We finally have the devices and the networks that make this possible.” And instead of installing a wireless plant infrastructure, users can even leverage commercial mobile data networks where it makes sense. “All you need is a connection back through the firewall, a data plan, and away you go.”
Smart handheld devices, of course, have been around for some time—streamlining data-gathering tasks during operations and maintenance rounds. But with wireless connectivity comes the ability to continuously synchronize data as workers move from point to point. There’s no need to dock the device at the end of the shift; information moves and updates immediately.
A growing class of worker mobility applications is allowing plant personnel to readily access the information they need, wherever they are in the plant.
Another and often critical class of wireless plant network applications involves real-time location awareness. That is, the ability to know where your people and your mobile plant assets are located at any given time. In the case of a safety incident, the ability to know immediately where all your employees are facilitates safer and more efficient mustering. The wireless application replaces clipboard tracking, allowing for quick, automated roll-call during an emergency.Location tracking and safety mustering.
Tracking the location of high-value equipment can be a boon to maintenance productivity. Further, when paired with a growing range of mobile worker applications, location awareness could even be used to manage a particular operator’s permission levels relative to their specific location in the plant.
Video. Because broadband plant wireless networks are based on commercial IT networking technology, they can readily handle a range of signals more common to the telecom world, namely wireless video and voice. Video applications include both process monitoring and security applications – for the video monitoring of flares, for example, or for complying with perimeter security monitoring requirements.
Bridging. The higher bandwidth of plant wireless networks is required in the bridging of two control system areas into one network.
“A wireless segment is an effective means of integrating two remotely located control systems,” says Peterson. The wireless bridging of two areas of control systems may be essential when the systems are located across bodies of water or are separated by terrain that is too difficult or expensive to trench for cable.