At the recent ARC Forum in Orlando, Emerson Process Management president John Berra made a major announcement about their future direction for wireless sensor technology. Based on a message of achieving increased return on investment for automation projects, particularly for underutilized HART field instruments already installed in the field, Emerson announced its new direction for field instrumentation based on wireless mesh networks for use in process plants. Specifically designed for applications in remote areas with distributed assets, near-plant applications such as tank farms, and in-plant applications, the new offerings will address key requirements for process plants such as security, power management, and conformance to standards.
Berra stated that the new mesh wireless offerings would address key issues such as encryption, authentication, verification, anti-jamming, and key management on the security side, which are primary concerns for process industry users and major hurdles to adoption today. To address the issue of power, the new sensors will treat power “like gold”, operating on ultra-low-power embedded radio technology and incorporating unique power management, advanced battery technologies, and power harvesting techniques such as solar cells, although the specific embedded technologies were not disclosed. According to Berra, the “power life of devices should be at least 10 years”. True to form for Emerson, the devices will also incorporate standards as they emerge, such as the HART wireless standard and SP 100, but again the specific underlying technologies were not disclosed.
According to Berra, Emerson's wireless mesh networking devices will reduce the cost of implementing field instruments by 90 percent due to the elimination of cabling and related equipment and installation costs. Existing HART devices that are already installed in the field, most of which do not avail themselves of their embedded diagnostic technologies and instead sit idle as conventional 4-20 mA devices, can utilize a small module that will be offered by Emerson to incorporate wireless functionality. This will allow users to take advantage of the full diagnostics functionality of HART devices, without the need for installing multiplexers or other hardware and wiring infrastructure that would other wise be necessary to integrate the HART devices with the control system.
The new technology will be available in mid-2006 with a “technology suite” of offerings, including pressure devices, temperature devices, and integration with DeltaV and Ovation control systems, and AMS plant asset management applications. Devices for flow measurement, level measurement, and analytical instrumentation are also on the way, as are digital valve controllers. Berra stated that five major oil company customers are already using the technology, as are two leading industrial gas companies, and that the technology is 99.9 percent reliable in the "canyons of metal" that characterize process plants. The unique mesh networking capabilities are also adaptable even in situations where large moving metal objects, such as trucks, could block the line of sight from sensor to base station because the device simply forms a new wireless connection path to the next nearest device.