“All of that energy gets discharged into the piping, and it can damage the pipe, causing leaks and any number of not-very-pleasant problems,” he said. “So, we use accelerometers with the vibration sensors to detect liquid hammers. They can tell us if a valve is broken or something is wrong with the system.”
Wolf said it was a long process to find sensors that met the company’s three priorities. The sensors had to:
- Be inexpensive, so they could use a lot of them to get the best possible view of what is happening in the giant warehouses.
- Be battery-powered so they could be put anywhere. And the batteries had to be long-lasting.
- Function in an “extremely challenging radio environment.”
“We found a lot of sensors, but the batteries might run out every couple of months. That’s no big deal if you have easy access to the sensors, but if I have a 500,000-sq.-ft. warehouse with several hundred of these things in it—often very high up in the rack—I don’t want to be replacing batteries all of the time,” he said. “So, Monnit fit the bill. They were reasonably priced. They had good technology and weren’t trying to send so much bandwidth on a high-frequency radio signal.”
Lineage currently uses approximately 1,500 AA battery-powered wireless sensors from Monnit across a few of its facilities, and they look to expand that into many more buildings in the near future. A sensor is placed every few meters to create a matrix and produce live temperature maps. The sensors gather data and send it to Monnit’s cloud system. Monnit then pushes the sensor data to Lineage for it to create the temperature maps.
“Monnit’s cloud system basically executes a web address that has embedded data in it. So, we use that feature to send the data to Amazon Web Services. And in there, we do all of the processing and visualization,” Wolf said.
The process is automatic, he said. As the sensors report, the data gets updated and the maps get updated. One map is on a television in the building so the crew on site can see what the thermal condition of their building looks like.
Data collected from Monnit temperature sensors is used to create a thermal map that shows the temperatures in Lineage Logistics' warehouses
Using temperature sensors to reduce energy costs
It costs hundreds of thousands of dollars to refrigerate a warehouse. Wolf said the power bill for Lineage’s biggest facility during peak months is $450,000. The energy usage during that time is about 9.5 megawatts, “which is a small city,” Wolf said.
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