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Power Distribution Units 101

by | Jun 17, 2020 | blog | 0 comments

What is a PDU and what Kind do I Need?

A Power Distribution Unit (PDU) is a device meant for controlling electrical power in a data center. PDUs can manage and control energy consumption in everything from small IT environments to a large, critical infrastructure. A PDU can help eliminate downtime, increase efficiency, and monitor power usage. Available in a variety of configurations, picking the right PDU depends on your business and power needs.

Types of PDU

To find out which features will be the most valuable to you, consider the various types of rack PDUs.

Basic PDU

Most people are familiar with a basic PDU. It’s a large power strip designed for standard electrical outlets. This type of PDU has no monitoring or remote capabilities.

Metered PDU

A metered PDU distributes network-grade power and offers remote monitoring and control capabilities. This helps users optimize load levels and prevents overloads.

Vertiv Basic PDU for Data Centers
Monitored PDU

Like its metered counterpart, a monitored PDU distributes network-grade power and supports local management. Monitored PDUs can also monitor power distribution with local and remote monitoring options. This additional functionality helps users prevent downtime that’s typically caused by overloads and other power events.

Switched PDU

A switched PDU distributes network-grade power and allows users to toggle power on and off for individual outputs.

APC Metered Rack PDU
Automatic PDU

An automatic PDU further eliminates downtime by automatically switching to a secondary power source if the primary fails or requires maintenance.

Hot-Swappable PDU

With a hot swap PDU, you can manage repairs or replacements without taking your network offline. The primary input plugs into an online UPS system, the second input plugs directly into a wall outlet. A manual transfer switch allows the load to be shifted from the UPS to direct primary power. You can then power down the UPS and remove it for repair or replacement while connected critical equipment remains powered and operational.

How Should I Set Up My PDU?

Here are the top considerations when setting up your PDU.


Your PDU location will depend on your IT environment and unique needs. PDU models are available vertical or horizontal and can be mounted in a rack enclosure, on a wall, or under a shelf.

Input Power Information

Depending on your building type, you’ll either have single-phase or three-phase power. Single-phase power will alternate between negative and positive voltage. This means the wave has zero voltage when moved from positive to negative and back. Most office power distribution is single-phase.

PDU power outlets

Three-phase eliminates the moments of zero voltage by offsetting three simultaneous waves. Three-phase power is common in commercial and industrial environments.

Number of Outlets

The number of outlets you’ll require depends on the number of devices you need to connect. Keep in mind the devices that have more than one plug, or devices that must be plugged into another as that may change the number of outlets needed. Don’t forget about devices such as lights or cooling fans and leave room for additional devices to be added in the future.

Need help selecting the right PDU? CEG can help!

Across the country, data centers, healthcare facilities, school campuses, manufacturing plants, and many other critical facilities have looked to CEG for help in choosing the right PDU and UPS systems for their environments. Ready to get the most from your PDU? CONTACT US today!



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