For years, large supervisory control and data acquisition (SCADA) systems have suffered from an annoyingly simple vulnerability: backup batteries in radio-signal extenders can die, causing a loss of communication. One large utility says a new monitoring device from Ventev Wireless Infrastructure solves the issue.
The SCADA for Southern Co.'s electrical grid is a series of devices that sends signals to each other via radio, says Bob Cheney, team leader for the power-delivery test lab at the utility, based in Atlanta. If two of these devices, called "preferred sources," are close enough physically, they can communicate directly with one another. If not, they need repeaters, or radio boosters, to extend the signal. If a preferred source loses power, the grid loses power, says Cheney. So, preferred sources are heavily monitored. "When the batteries are dead, we'll know," he says.