The industrial sector uses a variety of existing wireless standards, such as ZigBee and Wi-Fi, as well as a mix of proprietary technologies. But two projects from ISA and IEEE are leading to wireless standards specifically for industrial applications.
ISA
The ISA is making the bigger effort with ISA100 Wireless Systems for Industrial Automation. The group formed a standards committee in 2005 to define procedures for implementing wireless systems in the automation and in the control environment at the field level. The idea is to create standards for process automation, factory automation, transmission and distribution (long distance), and RFID.
The standard under development is called SP-100a. It is based on the IEEE 802.15.4 standard in the 2.4-GHz band but with its own network layer for mesh and other topologies. The standard is set up to communicate with all the current popular industrial networking technologies like HART, Foundation Fieldbus, Modbus, Profibus, and Common Industrial Protocol (CIP).
One big problem is that 802.15.4 does not support the Internet Protocol, so you need specialized gateways or other solutions to connect to the Internet. One potential solution is to use a new standard developed by the Internet Engineering Task Force (IETF) known as IPv6 over Low-power WPAN (6lowpan).
This protocol allows IPv6 packets to be sent to and received from personal area networks (PANs) like the 802.15.4. According to Geoff Mulligan, one of the chairs for the 6lopan standard working group, the SP-100a committee has agreed to adopt this IETF standard as part of its protocol.
Industry users and suppliers recently established the ISA100 Wireless Compliance Institute to initiate testing and certification procedures for SP-100a products to come. To check on the latest progress of the standard effort, go to www.isa.org/ISA100.
IEEE
The IEEE 1451 project seeks to establish a set of open, common, network-independent communications interfaces for connecting all sorts of industrial transducers, both sensors and actuators. A key feature is the definition of Transducer Electronic Data Sheets (TEDS), which is a memory device attached to the transducer that stores transducer identification, calibration, correction data, measurement range, and manufacture-related information.
The functionality of the TEDS is independent of the physical communications media between the transducers and the network node known as the Network Capable Application Processor (NCAP). The 1451.5 standard defines a transducer to NCAP interface and TEDS for wireless transducers.
The wireless standards being considered for this standard are 802.11 (Wi-Fi), 802.15.1 (Bluetooth), and 802.15.4 (ZigBee). For more details on this standards effort, go to grouper.ieee.org/groups/1451/ and ieee1451.nist.gov.
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