How Many PDU Outlets Do You Need, and What Type? Find Out.

Jan 24, 2019

4 min read

What This Article Covers

Key Considerations for Selecting PDU Outlet Types in Modern Data Centers

Power distribution units (PDUs) are critical components in data center infrastructure, providing reliable power to rack-mounted equipment. Selecting the appropriate PDU outlet types ensures compatibility with various devices and supports high-density deployments. Understanding PDU connectors helps prevent mismatches and enhances operational efficiency.

Common PDU outlet types include IEC 320 C13 and C19 variants, which cater to different power requirements and equipment profiles. C13 outlets typically power smaller servers and network devices, while C19 outlets handle higher-amperage equipment like blade chassis. As power demands evolve, newer plug types such as C15 and C21 are emerging for advanced applications.

When planning PDU configurations, consider the mix of outlet types to support current and future hardware needs. A combination of C13 and C19 outlets offers flexibility, as C19 receptacles can accept both C14 and C20 plugs. This approach future-proofs your infrastructure against changing technology trends and increasing power densities.

Locking mechanisms on PDU outlets prevent accidental disconnections in high-vibration or busy environments, ensuring continuous operation. Standard power cord compatibility reduces total cost of ownership by avoiding proprietary cables. These features are essential for maintaining reliability and minimizing downtime in critical setups.

Chatsworth Products offers eConnect® PDUs with QuadLock outlets, supporting multiple outlet types including C13, C15, C19, and C21 in a single unit. This innovation simplifies power management and adapts to diverse equipment, from traditional servers to AI-intensive workloads. Explore CPI solutions to optimize your power distribution strategy with confidence.

As processing demands increase at every cabinet, your cabinet power distribution strategy becomes a key factor so that the highest level of availability and efficiency are achieved with minimum management overhead.

But here's the challenge: How many outlets do you need—and which types—when your equipment mix keeps evolving?

The answer depends on the kind of hardware you're powering, and increasingly, how adaptable your infrastructure is to future change.

Matching Outlet Type to Equipment

In most data centers, high-density cabinets typically fall into two categories:

Rack Full of 1U/2U Servers in Taller Cabinets

These cabinets typically have a high number of lower amperage servers that are powered through IEC 320 C14 connectors. In this case, the rack PDU should provide a high quantity of IEC 320 C13 outlets—some intelligent PDUs offer up to 60 C13s to support tall cabinets.

Rack Filled with Blade Chassis or Modular Network Switches

These cabinets would typically have fewer pieces of equipment, all being powered through multiple power supplies, each utilizing one or several C20 connectors. For these deployments, you need intelligent rack PDUs that have a high number of C19 outlets.

Planning for Today—and Tomorrow

Ideally, you'd choose your PDU after you've picked out all the IT equipment going into your cabinet. That way, you can make sure you have the right number and types of power outlets.

But, things don’t always happen in that order. Sometimes you need to choose a PDU before your full hardware list is finalized.

That’s why flexibility is critical.

Here’s what to keep in mind:

Go with a mix of outlet types. A good combination of C13 and C19 outlets will support a range of equipment and give you room to grow.
C19 outlets offer more flexibility—they can power devices with either C14 or C20 plugs, while C13 outlets can only handle C14.
Typically, smaller gear like 1U or 2U servers use C13/C14, while larger, higher-power equipment like blade servers or network switches use C19/C20.
As workloads become more power-hungry (think AI, HPC, or GPU-heavy setups), you may start seeing newer plug types like C15 and C21.

It pays to choose a PDU that can support multiple outlet types and higher power densities.

No matter whether you’re using C13, C19, or a mix of both, it’s important to choose outlets with a locking feature to prevent accidental disconnections—especially in busy or high-vibration environments.

To save on overall upfront costs of the entire solution, locking outlets should be able to support standard power cords. If you select a model that uses proprietary power cords, you will have the added expense of sourcing a proprietary power cord for each powered device.

Introducing eConnect® PDUs with QuadLock Outlets: One PDU. Four Outlet Types. Full Flexibility.

To meet these evolving needs, Chatsworth Products now offers —a first-of-its-kind solution combining flexibility, reliability, and simplicity.

With QuadLock, you get:

Four supported outlet types—C13, C15, C19, and C21—in a single PDU, reducing complexity and ensuring compatibility with virtually any rack-mounted equipment.
Built-in locking on every outlet, helping you prevent accidental disconnections without needing proprietary cables.
Support for high-density, high-power deployments, including up to 57.5 kW per cabinet and up to 100A inputs—ideal for liquid cooling and AI-intensive workloads.
Standard power cord compatibility, reducing total cost of ownership and simplifying deployment.

A Smarter Way to Power Your Rack

As power demands grow and rack configurations evolve, the need for outlet-level flexibility becomes more urgent. CPI’s eConnect PDUs with QuadLock Outlets help you solve today’s needs—and tomorrow’s—with a single, streamlined solution that adapts to whatever comes next.

Explore our today.