When I met with Tim Cutler of Cirronet during Sensors Expo a couple of weeks ago, he told me that many of his customers are buying his products to replace wired sensor installations in industrial plants. Holy smokes, I thought: "Are you saying that people are pulling out wired installations and replacing them with wireless?"
"Not exactly," he replied, explaining that when legacy sensors fail, people are opting to replace them with wireless devices instead of with exact-match replacements. And by the way, he added, the wireless replacements ease the burden of reconfiguring equipment layout within a facility when that becomes necessary or desirable.
A couple of recent articles in Sensors have covered retrofit-not of industrial facilities, but of public buildings. The principles are the same, and the examples demonstrate what Cutler alluded to: that wireless networks have much to offer this type of endeavor.
An in-depth case study in our May issue tells of how the Horry County school district in South Carolina upgraded building control systems, and details how the school system's energy manager, Paul Hucks, was able to overcome the challenges of a short timeframe, tight budget, and structural impediments to wireless—among other things.
The project was not cut and dried; "The answer of how this or any other RF technology is going to work is always 'it depends.' It depends on the facility's physical characteristics and how robust the RF technology is," said Jeff Raimo, product manager for Siemens Building Technologies, which helped Hucks tackle his project. "During beta testing, every facility type was unique and presented a new test bed for the technology," he explained.
But the mesh networking technology helped the team meet its objectives—and then some. Hucks said he wanted to "be able to add a unit, move a classroom, or add a water heater without having to go out there and run a LAN cable." He got his wish.
The June App Snaps department presents a shorter story with a similar outcome about a health clinic in Chicago that determined a need to monitor air temperature and energy use. Here, building codes and steep costs seemed to be deal breakers, but mesh networking allowed the installation of a robust network (nearly 50 sensors and a Web-accessible control system) quickly.
Desire Becomes Need
In both cases, the flexibility Cutler referred to—the ability to "rearrange furniture" without undue pain and expense—is icing on the cake. But I suspect the facilities managers will, over time, come to regard this capability more as a need than simply a desire.