Emerson launches smart wireless system
Emerson launches smart wireless system
Following extensive field trials in the USA, Emerson Process Management, part of the $17 billion Emerson group, has just announced the European launch its new in-plant “Smart Wireless” system. As an extension to Emerson's existing PlantWeb® digital plant architecture, Smart Wireless is the industry's first process monitoring system to use self-organising network technology.
Emerson began research and development into smart wireless system technology in 1998 and argues that, by combining wireless networks and gateways with wireless-enabled “Rosemount” measurement transmitters, users can gain a better understanding of their processes and identify opportunities for improvement. Further, the system can improve the response times to safety incidents, minimise emissions, help to protect the environment and extend the life of assets through proactive maintenance. A system schematic is shown in Figure 8.
Figure 8 Schematic of the Emerson “Smart Wireless” system (Courtesy of Emerson Process Management)
The heart of the system is the self- organizing mesh network which uses time synchronised mesh protocol (TSMP), a communications protocol pioneered by Dust Networks. Emerson considered a number of different wireless sensor networking technologies, including the widely publicised ZigBee.
However, after testing them in real industrial environments, they settled on TSPM, as this was seen as offering the best combination of range, reliability,data rates, security, battery life and ease of use. It can operate at both 900MHz (North America) and 2.4GHz (Europe and Asia) frequencies. The 900MHz system can achieve an outdoor communication distance of up to 200m whilst at 2.4GHz, systems can operate over distances of up to 300m. The high system reliability of TSMP arises from features which include time synchronized communication using the time division multiple access technique, frequency hopping, automatic node joining and network formation, fully redundant mesh routing and highly secure message transfer.
During three years of field trials by selected users in the USA, network reliability of 99.9 per cent was reported. This is primarily due to the self-organising nature of the TSMP technology, as in the event of a temporary obstruction blocking a direct connection, the network automatically re-routes the signal to an adjacent device. A critical benefit of this (and any) wireless sensor network is the reduction in the labour and hardware costs associated with installation and during the trials users reported that these fell by up to 90 per cent.
Further, industry estimates suggest that there are as many as 20 million HART-enabled devices running in plants today whose health diagnostics are“stranded” by 4-20mA hard-wired analogue systems. To overcome this,Emerson will shortly be launching a Smart Wireless upgrade module which will allow the diagnostic capabilities in these devices to be fully exploited.
To assist new users, Emerson is offering a “Wireless SmartPack Starter Kit” which includes five Rosemount wireless process transmitters (for any combination of flow, temperature, level or pressure sensing), a wireless communications gateway and the AMS Intelligent Device Manager software for predictive diagnostics from wireless devices.
Emerson and Dust Networks are working with equipment vendors, end- users and industry associations, including the Wireless HART working group of the HART Communications Foundation and ISA's SP-100, to develop wireless networking standards that will meet the future industrial monitoring and control requirements.
