Last year representatives from the Open DeviceNet Vendor Association (ODVA; www.ethernet-ip.org) and the Interface for Distributed Automation (IDA; www.ida-group.org) Group agreed to copromote with the Industrial Automation Open Networking Alliance (IAONA; www.iaona.com) the EtherNet/IP (Industrial Protocol) networking protocol for industrial automation applications.
As an open industrial networking standard, Ethernet/IP supports implicit messaging (real-time I/O messaging), explicit messaging (message exchange), or both and uses commercial off-the-shelf Ethernet communication chips and physical media. Because Ethernet technology has been used since the mid-1970s, Ethernet products are available at low cost from a number of vendors.
EtherNet/IP is an open network that uses the IEEE 802.3 Physical and Data Link standard, Ethernet TCP/IP protocol suite, and a UDP/IP (User Datagram Protocol) to provide data transport needed for real-time data exchange. In addition, the Control and Information Protocol (CIP) uses the ControlNet and DeviceNet standards to provide a common application layer for real-time I/O and peer-to-peer messaging.
Typical devices communicating across an EtherNet/IP network include ma-chine-vision systems, PLC processors, robots, and I/O and I/O adapters in applications such as plant management and material-handling systems. Now, a number of companies are introducing products based on the EtherNet/IP standard.
Allen Bradley/Rockwell Automation (Milwaukee, WI), for example, has expanded its PanelView family to include EtherNet/IP operator interface terminals. With the addition of EtherNet/IP, the PanelView 550T and PanelView 1400 EtherNet/IP terminals can communicate to multiple PLC-5E, SLC 5/05, and ControlLogix processors, and other EtherNet/IP devices using the CIP protocol.
For factory applications that demand machine vision, Cognex Corp. (Natick, MA) has also added EtherNet/IP to its In-Sight family of networkable vision sensors. This enables direct, real-time communications between In-Sight vision sensors and other factory-automation devices over Ethernet. EtherNet/IP-compatible products include the In-Sight 1000 and 3000, the In-Sight 1010 barcode reader, and the In-Sight 1700 wafer-reading sensor.
Joe Crompton, vision project manager at ABB Robotics (Norwalk, CT), also plans EtherNet/IP support for the company's FlexPicker and other robots. According to Crompton, the company sees a tremendous need for the standard and is moving in that direction, although any implementation will not occur for at least the next six months.
While EtherNet/IP provides ControlNet/DeviceNet objects on TCP/IP, other Fieldbus organizations have already produced Ethernet TCP/IP application layers of their protocols. These include Modbus/TCP, the Modbus protocol on TCP/IP and Profibus on Ethernet. And, even though standards such as DeviceNet can supply power and communications through the same cable, EtherNet/IP remains an opportunity for the ODVA to leverage their common application layer and meet the demand for a low-cost, high-speed industrial Ethernet standard.