Charles R. Bourn, Jr., P.E., Carter & Burgess Inc. Fort Worth, Texas

UPS—What’s New and What Works

In order to fulfill its primary function—delivering power from a few seconds to as long as 10 minutes or more—an uninterruptible power supply (UPS) must continually monitor the power coming into a facility. Ideally, when the line power goes out, even for 1/120th of a second, which is half a cycle of 60-Hertz AC power, the UPS takes over and the facility's equipment doesn't even notice.