Some plant operators have adopted Ethernet for this reason alone. “Ethernet fits wireless like a glove,” says Harry Forbes, senior analyst at ARC Advisory Group Inc., in Dedham, Mass. “That will make Ethernet big because people are now carrying laptops and handheld devices and their equipment is all speaking 802.11 [protocol].”
Forbes believes that the wireless connectivity in an Ethernet network will open up the possibility for a broader network that includes equipment that couldn’t previously be easily connected to a network. “There are things you can do with wireless that you can’t do with cabling. You can’t deal with motion without using wireless,” says Forbes.
“Production systems with robotics require periodic replacement because of the cabling harness. If you have things that move, it works better if you can use wireless connectivity.”
Wireless networks allow for less expensive networks when running cables becomes prohibitively expensive. “A lot of our customers are in water and wastewater processing, and they say it takes $100 per foot to run a wire to a tank. So they use wireless connectors,” says Tom Edwards, senior technical advisor at Opto 22, a Temecula, Calif., vendor. A wireless network also frees the operators to roam through the networked system while staying connected.
The one significant downside to wireless connectivity is that it doesn’t work in all environments. “There are some issues with wireless that still need work,” says Francisco Tacoa, North American product manager for Weidmuller Advanced Connectivity Solutions, at The Weidmuller Group, in Richmond, Va. “With wireless, you can’t have an environment that is susceptible to electromagnetic interference.”