Given the rapid adoption of wireless as an automation network tool–its use has grown much faster than did Ethernet initially–I spoke recently with Bill Conley, lead wireless design engineer at B&B Electronics. Bill is a great person to speak with about wireless, considering he has been involved with wireless since its early days, winning a Best of Sensors Expo 2002 award for his wireless sensor transceiver technology. Bill was also among the first third party certified design engineers to work with Aerocomm’s and MaxStream’s 900 MHz wireless products.
When I spoke with Bill, I wanted to get an insider’s sense of the current arc in wireless technology as an automation network tool, from its starting point to its current best practice and application.
Following is a transcript of portions of our conversation.
DG: When did the wireless trend first begin to really take off from a systems design point of view?
BC: Wireless has been building since about 1994. B&B recognized the trend early on, and acquired Advanced Embedded Systems in 2006 to accelerate its foothold in the industrial data acquisitions market. (Note: Advanced Embedded Systems was a wireless communication products supplier to the sensor, controller, and embedded markets).
DG: Have any particular industries been the leader in deployment of wireless technologies as part of an automation network?
BC: Adoption has been fairly broad. But the oil and gas and wastewater treatment industries have been the clear leaders in terms of monitoring and control. Other markets include tank farm monitoring and inventory control. B&B sees growing interest in wireless from a systems design perspective as more products offer higher resolution at lower cost, lower profile, etc. For system designers, wireless eliminates running a lot of wires back to a PLC. Much of what we’ve done with systems designers has been in industrial wire replacement applications, where it’s essential to support many industry protocols such as Modbus RTU, Modbus TCP/IP and Rockwell’s Ethernet/IP.
DG: In terms of adoption, where is wireless at on the new technology adoption curve in terms of automation use?
BC: We’re on the upswing of the adoption curve, and the potential is huge in my opinion. Even though interest and use has grown quickly, the industry is only beginning to tap the potential of wireless applications.
DG: Based on what you’ve seen so far, what have been the roadblocks to adoption of wireless for most systems design engineers?
BC: Speed and security. For standard I/O use, speed is not a big issue–wireless I/O acquisition speeds are reasonable, but could always improve. For wireless transmission of Ethernet, we’re on the edge of being equal in terms of speed vs. wired systems. Of course, the industry will demand ever-increasing speed as it matures.
When it comes to security, the choices are: proprietary encryption and known encryption standards such as AES (Advanced Encryption Standard) 128-bit and 256-bit encryption–the standard adopted by the U.S. government. Proprietary encryption schemes can make it difficult to prove that a system is properly protected. Employing industry-accepted encryption standards would alleviate security concerns.
Firewalls have also been a big issue in terms of wireless security. B&B Electronics is currently developing gateways that can collect wireless I/O data from many end-nodes and serve the data to an end user via the Internet. The industry is moving in this direction. IT departments are leery of opening up their firewalls to accommodate other departments’ wireless data. One solution that doesn’t rob IT of too much of its bandwidth is to push data using XML and FTP via routers.
DG: Considering where things stand with wireless technology today, where wouldn’t you advise using wireless?
BC: Really, nowhere. Wireless is already broadly applicable to both consumer and industrial markets, from wirelessly monitoring your refrigerator’s temperature to monitoring and control of a nuclear power plant. B&B sees companies moving away from wired systems because of installation and maintenance headaches.
Battery life needs to be taken into account during systems design. If the system you’re designing requires frequent, power-intensive data transmission, the resulting frequent battery-changing partially defeats the purpose of having a low-maintenance wireless system. However, the trend we’re seeing for battery-operated devices is to only “report by exception,” which dramatically decreases transmissions and extends battery life. In those cases, unless there are a lot of exceptions, battery power is fine for wireless systems.
For information about B&B Electronics’ new Zlinx Xtreme industrial automation/wire replacement solution, which addresses some of the issues (speed, security, etc) that Bill discussed, click here.