Embracing Wireless Technology for Industrial Automation

Arun Veeramani

With today's pressure to attain a competitive edge and cost-efficient operations, the automation sector is striving to optimize its systems by turning to IT technologies to get real-time information from the factory floor. Consider the benefits of using wireless networking.

Wireless Networking
The key to getting plantwide real-time data is communication between the machines on the factory floor and the enterprise. As wireless networking has become more commonplace, its performance, reliability, and security has matured to make the technology viable for industrial measurement and monitoring applications.

The desire to minimize cabling costs and the difficulty of running wires to every nook and corner of a plant have resulted in industrial automation's slow march toward wireless technology. Engineers and managers have quite a few wireless standards at their disposal, from 802.11 (Wi-Fi) to ZigBee. Although Wi-Fi networks have become standard fare in corporate offices, offering good speed and flexibility, a ZigBee network is better suited for control and monitoring applications because of its lower power consumption and cost.

One major concern of users is the security of the network. With data being transmitted over radio waves, there are few means of physically restricting network access. Both Wi-Fi and Zigbee, however, use 128-bit AES encryption. This measure is so strong that the National Institute of Standards and Technology recommends its deployment by government installations. With hardware vendors choosing one standard over the other, it's important that you choose open and flexible software that can communicate with a number of wireless standards.

There's also value in a hybrid network topology that combines Ethernet with wireless networking. Ethernet has been widely adopted in the IT and automation sectors, so it's easy to connect gateways that collect data from wireless sensors and data acquisition devices to the existing infrastructure. Many industrial fieldbus and communication standards, such as Ethernet/IP, EtherCAT, PROFINET, and Modbus TCP, use the Ethernet physical layer. Keep in mind that, even though these protocols use the same physical layer, you need fieldbus gateways that map one protocol to another.

It is not outrageous to suggest that automation engineers can set up wireless measurement and monitoring systems with minimal help from their IT department. The ability to use existing networking infrastructure and choose hardware and software that are open and flexible enough to take advantage of these IT technologies is very important, as the line between IT and automation begins to blur.