One of my pet peeves is lumping all wireless types together and treating them as one. Wireless is not one monolithic thing. I see four types of wireless in industrial automation:
1. Backhaul (as I think ISA characterizes it). Typically this is long distance radio bringing data from an RTU perhaps at a wellhead to a central control room. The radios tend to be proprietary but the protocol is often Modbus.
2. Process Instrument networks. WirelessHART and ISA 100.a specify their respective protocols and radios. WirelessHART is working with PI (PROFIBUS and PROFINET International), and Fieldbus Foundation to coordinate their activities and ensure interoperation. This group is called the Wireless Cooperation Team.
3. Discrete sensors and actuators. While process instruments are characterized by slow cycle times (seconds or fractions thereof), discrete devices typically operate much faster (milliseconds). PI is working with leading discrete vendors in developing a wireless standard for discrete sensors and actuators. The protocol will be IO-Link which is a growing wired sensor and actuator technology. Coexistence with the other wireless technologies will be assured.
4. Wireless Backbone. This is how I characterize WiFi and Bluetooth as used by the Industrial Ethernets. Any plain old Ethernet should run just as well on wireless standards like 802.11a, b, g, and n. PROFINET, of course, does.
Hunter and I did a webinar on PROFINET and wireless; it’s still available in the archive. The 2010 PROFINET one-day training classes have a section devoted to the topic too. Speaking of PROFINET one-day training classes, our first of the year is in Atlanta next Tuesday. Registration has surpassed 110, but we were able to secure larger space, so still have room for more. Register for Atlanta here. I hope to see you in Atlanta or one of the other nine PROFINET cities.