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Power Distribution Unit (PDU)

What is a Power Distribution Unit (PDU)?

Power distribution units (PDUs) can be useful when you need to power many devices at data centers. Multiple devices, anywhere from 4 to over 60, can be plugged into the PDU, which will then allocate power appropriately.

How Does a Power Distribution Unit Work?

Much like a breaker panel that someone may have at their house, a PDU will power multiple devices by attaching to a main power supply, either a utility power outlet, uninterruptible power supply (UPS), or generator. From there, the PDU distributes power through its multiple outlets to the devices that will use the power. The devices that are plugged into the PDU may also benefit from power metering, surge protection, and overload protection if the PDU has those features.

Why are Power Distribution Units Important?

Data centers that are looking to improve uptime and efficiency can do so with the help of a combinatiuon of a PDU and UPS. These units can also protect equipment from damaging power surges and overloads. Plus, most PDUs can help you remotely manage the usage of power devices and monitor and troubleshoot any potential problems with power.

Types of Power Distribution Units

The two main types of power distribution units are outlet PDUs and metered PDUs. Outlet PDUs typically located within the customer cage or rack and are simpler in design, offering multiple electrical outlets that devices can be plugged into. Metered PDUs are found on the data center floor itself,  providing features, such as remote access and power monitoring at the data center or customer level. They can often be controlled remotely and report on the amount of power different devices are using.

What is the Difference Between PDUs and UPSs?

While PDUs and UPSs both offer important features that help power a data center, they serve distinct purposes. An uninterruptible power supply (UPS) conditions the power and ensures that devices can keep running, even during a power outage. When a device experiences a disruption to its main power source, this will trigger a switch to the UPS, which runs on stored battery power. Depending on the size, battery type, and load on the UPS, it may be able to run for hours or even a whole day.


Unlike UPSs, PDUs don't supply their own power. However, they can protect against overloads or power surges that may activate a UPS in the first place. PDUs can also be attached to uninterruptible power supplies. Having both in place, together they can provide better coverage in response to an outage or other electrical event.

What are the Benefits of Power Distribution Units?

Data centers, whether carrier-neutral or carrier-specific, can benefit from the use of PDUs in a few ways. First, they can make managing the power to devices easier by providing fewer, more centralized locations from where devices are powered. The consolidation offered by power distribution units can also improve the efficiency of the data center and reduce the amount of total power wasted. Finally, especially with more advanced PDUs, data centers can experience greater uptime and a lower risk of outages.

Power Distribution Units at TierPoint Data Centers

To be considered reliable, devices and equipment used at data centers need to have multiple forms of redundancy via power distribution units, uninterruptible power supplies, and backup generators. TierPoint offers this redundancy at all our data centers, offering peace of mind to our clients.

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