Even though ARC Advisory Group, a Dedham, Mass., analyst firm, recently released a study proclaiming that the wireless sensor network known as ZigBee may not be ready for industrial use, wireless networking based on other self-organizing “mesh network” schemes appears to be gathering momentum. Two process control companies revealed budding applications at their respective user conferences that incorporate wireless mesh networks as part of their solutions.
A working demonstration of a transmitter fitted with wireless mesh networking radios was featured on the exhibition floor at the Emerson Process Global Users Conference, Oct. 3-6 in Orlando, Fla. In addition, engineers from a refinery presented a paper about the successful beta installation of these transmitters. Spokespersons for Austin, Texas-based Emerson stressed that this is not yet a released product.
Invensys Process Systems, the London-based automation conglomerate, at its User Conference the same week in Houston unveiled a partnership with network gateway supplier Apprion, Moffett Field, Calif. The companies have combined to develop a wireless sensor network using Apprion’s wireless gateway to multiple protocols and Invensys’ mesh technology. The system backbone is based on the IEEE 802.16 standard of the Institute of Electrical and Electronics Engineers, also known as WiMax, while wireless mesh networking connects the sensors. Engineers presented an overview of a beta installation at a plant operated by Pittsburgh-based PPG Industries. The beta test is on hold due to the unfortunate hurricane strikes at the plant, in Lake Charles, La., which left two-thirds of the facility swamped.
The promise of wireless sensor networks is the ability to place many more sensors in a plant due to the relatively inexpensive installation costs. These additional sensors would provide substantial information about plant status, enabling better decision-making by managers and operators.
Wired mesh too
Meanwhile, Echelon Corp., supplier of LonWorks control networking, launched the Pyxos FT chip. Designed to be built into the sensors and actuators embedded inside a machine, Pyxos FT chips extract information from the devices, relay control commands between devices and make the machine's control network status available to remote service centers and applications. These features are combined with self-organizing network capabilities. The chips use twisted-pair wiring to send both network data and power to sensors, actuators, devices and even building materials into which they have been embedded.