Uninterruptible Power Supplies Keep Trees from Stumping Power

By Consulting Specifying Engineer Staff March 16, 2005

According to the final report by a joint U.S.-Canadian task force, the power outage that was responsible for leaving nearly 50 million people in the dark in the United States and Canada during the summer of 2003 could have been prevented. With something as simple as “inadequate tree trimming” cited as one of the four causes of the massive power outage, what’s a network or facility manager to do?

That reality didn’t stump Cowan Bowman, technology coordinator for the Farmington Public Library in Farmington, N.M. “We try to stay up with technology whenever we can, and power protection is one of the areas where we can’t come up short,” said Bowman. Though tree trimming wasn’t on Bowman’s list when asked what caused most of the power outages at the library, “hitting a pole, end-of-life for transformers, and an occasional electrical thunderstorm” did make the list.

With a brand new 50,000-sq.-ft. facility, the library offers its community a place for visitors to flip through their favorite magazines, surf the Internet, see an art exhibit, listen to music and more.

Whether paper- or digitally-based, providing the latest information to library visitors is key. So is keeping the power and lights on. Bowman is responsible for managing the library’s computer network, which currently has about 100 computers for staff and visitors.

Aside from the basic physical layout of the library, the new facility design also incorporates the latest in digital technology. Fully networked with over 100,000 ft. of Cat 5 and Cat 6 cabling, the library is ready to provide the best in computing and communication with its sights on a gigabit local-area network.

“It’s my job to keep the network, computers and servers working,” he said. “One way that I’ve ensured continual service is to have uninterruptible power systems to protect us from power glitches.”

It’s important to note that not just a power outage alone can be damaging. Even when power does come back on, it usually comes in a surge and then goes back to nominal levels. Those surges can damage equipment too.

When setting up the UPS systems to protect the library’s automation system, which covers applications such as the catalog, services and inter-library loans, Bowman plays it safe. “To keep our network running smoothly, our UPSs are set up to last through a 30-minute power outage,” said Bowman. “As a matter of fact, the UPSs are running on half-load capacity, which gives us extra battery backup time and also allows room for equipment expansion.”

The Farmington library has numerous 1500-VA UPS units in both tower and rack-mount configurations. The rack-mountable units are designed for dense environments, where rack real estate is a premium. More true power (measured in watts) in a tighter form factor (measured in rack U-space) provides better performance while saving valuable rack real estate. Extended runtime modules support the UPS units for additional battery backup time. And option cards add extensive networking capabilities. Individual load segments can be set up to shift battery backup time to the most important computer devices should a power failure occur.

It’s also handy to be able to anticipate network or power problems. In a sense, the UPS systems have done just that. “The [UPS systems] actually give you both a visual and audio warning that a battery isn’t keeping a charge or that it’s getting to the end of its life. I’d rather find out beforehand that the batteries are old so that I can have them replaced before the next power mishap.”

For additional clarity and foresight, power management software also provides information about power conditions, health and status of the UPS and overall power environment. The software allows users to schedule system shutdowns, control power failure settings, and define UPS load segments to allow for maximum uptime of critical servers across the network. The software even provides the ability to configure redundant UPSs and system event handling, which allows users to establish power and environmental failure policies with programmed automatic responses.

And in keeping to its preparation for the future, the Farmington Public Library facility also has data rooms wired for high-line, 208 volts. “We wired some data rooms for 208 volts,” added Bowman. “When we start moving equipment into there, we’ll be able to get almost twice the power. And we plan to buy the 208-volt UPS units that fit those higher power outlets. I’ll be able to protect more equipment on those UPSs and get more power backup,” Bowman concluded.

Well, even if the tree trimmers don’t show up in the future, Bowman is weeding out the possibility of future power problems at the Farmington Public Library.

For more information about UPS from Hewlett-Packard, click here .