However, a variation of Ethernet, Power over Ethernet (PoE), is beginning to see more interest. Power is transmitted over conventional cabling, so components can be installed in spots where it’s difficult to add a power cable.
PoE saw minimal interest in automation applications when it first came out, largely because its 12-watt power limitation was insufficient for many industrial applications. But a version that delivers 25 watts was rolled out a couple years ago, making it more viable. That’s prompting users to plan for adoption, with help from suppliers who are beefing up their offerings.
“Today, its usage is fairly limited,” says Mike Hannah, product business manager for networks at Rockwell Automation (www.rockwellautomation.com).“Most applications have been in Internet Protocol cameras and wireless access points. But interest is expanding. More people are looking at it for inspection or to monitor safety zones. We’re getting ready to launch some PoE products.”
Customers prefer PoE over wireless networking alternatives because it doesn’t require batteries. PoE also provides the reliability and speed of wired connections. That’s prompting many equipment makers to expand their offerings to meet growing demand from customers.
“PoE is trickling down into industrial applications, it really is plug and play,” says Ken Austin, Ethernet marketing specialist for Phoenix Contact (www.phoenixcontact.com) of Middletown, Pa. “We’ve seen companies go from using it first for wireless access points. Now entire phone systems are based on PoE and many RFID [radio-frequency identification] readers use PoE. We’ll be coming out with more PoE support products in 2013."
>> Read Automation World's complete coverage on faster control operations: Switching to More Efficient Networks