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A CDE Definition

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power distribution unit

A device used in datacenters to distribute AC power to multiple servers and other equipment. Power distribution units (PDUs) range from simple 120v power strips to units that break out 120 volts from 240v and three-phase power. Advanced units are managed remotely via the SNMP management protocol or from a Web browser or other management console, causing outlets to be turned on and off at prescribed times and in a proper sequence for shutting down and powering up equipment. See power strip.

In the Rack
Most power distribution units (PDUs) are used to deliver power to rack-mounted equipment such as this basic 120v unit from APC. (Image courtesy of American Power Conversion Corporation.)

Wired to Go
This more advanced APC unit is connected to the network via the blue Ethernet cable so that outlets can be managed. (Image courtesy of American Power Conversion Corporation.)

power strip

An electricity distribution device that turns one AC wall outlet into several. Power strips may or may not include surge suppression circuits, and many strips leave room for the myriad power adapters that accompany products. See power distribution unit, power adapter and surge suppression.

Room for "Warts"
Many power strips leave room for one or more "wall warts;" slang for the power adapter blocks that come with many electronics products.

Save Energy
Even power saving mode uses electricity. Attached to a motion sensor (bottom), this Watt Stopper has two regular outlets and six that turn off when you leave the room. The computer can stay on, while lights, monitor and printer are shut off. (Image courtesy of Legrand Companies,

Designed for Racks
Power strips are widely used in equipment racks to distribute power to all the devices. Sophisticated units turn devices on and off (see power distribution unit). (Image courtesy of American Power Conversion Corporation.)

Personal Use Only

Before/After Your Search Term
POV-Raypower down
PoWpower Ethernet
powerpower good
power adapterpower line
Power BookPower Mac
power brickPower Macintosh
power cablepower management
POWER CPUpower margin
power cyclepower MOSFET
power cyclingpower on self test

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