Information

Questions to consider when selecting a PDU for your data centre 

1. What are the different types of receptacles or connectors used?

In most PDUs used in data centres, the sockets used are IEC 60320 standard sockets or in some cases Schuko or NEMA sockets. Commonly used sockets are IEC 60320 C13 or C19 types. For the required output of 10 amps, the C13 socket is used and for 16 amps, the C19 socket is used, both for 250 VAC.

As higher density data centres are required, the higher power requirements will also push up the temperature ratings of the sockets; the C13 and C19 sockets are rated at 70 degrees Celsius. For higher temperatures up to 150 degrees Celsius, higher standard sockets need to be considered.

2. How many outlets are there?

The number of outlets integrated into any PDU usually depends on the specifications provided by the customer, depending on the servers and other equipment connected in the server rack. Generally each branch is configured with a combination of C13 and C19 outlets, which determines the size and length of the PDU, but the total length of the PDU and the height of the server cabinet are limited. A standard and basic PDU will have 24 to 40 or more outlets in its configuration.

However, certain PDUs have different configurations. These PDUs tend to divide the circuit into various branches, each of which operates according to a fuse or its circuit breaker. This alternating phase PDU distributes power on a per outlet basis in the facility.

3. Are the outlets colour coded?

To ensure easy identification of circuits, it may not be necessary to integrate colour coded sockets unless specified by the user, but colour coding of branches and circuit breakers can be used to better identify branches or circuits. It also reduces the risk of overloads as it makes identification of circuit configurations easier. Since the outlets of traditional PDUs are grouped according to the branch of the configuration, high-density PDUs organise alternating-phase outlets to reduce wire clutter, simplify load balancing in circuits and allow more outlets to be integrated in the same space.

4. What is the footprint of the PDU?

Before finalising a PDU for a circuit, the footprint and its impact must be considered. That said, 0U PDUs are convenient and don't take up much space in the facility; considering their footprint, impact on heat dissipation, and cable management practices can help find the ideal configuration. Those with slimline designs adjust within a limited space while increasing airflow and operational efficiency within the circuit. When circuits use multiple PDUs to support power, analysing the footprint of the PDU becomes particularly important.

5. Does the PDU offer metering capabilities?

PDUs have integrated metering capabilities that significantly reduce the risk of circuit overload. It also helps data centre operators plan circuit capacity and optimise energy usage. Input metering PDUs monitor circuit breakers and phasing in real time to prevent any damage to the circuit. Outlet metering PDUs typically monitor electrical loads at the outlet level. Networked PDUs allow technicians to remotely view the collected data.

6. Does the PDU have switched outlets?

Switched outlets are a universal feature, which makes the application easier to access. It allows technicians to turn power on and off as well as remotely reboot devices and sort devices for power control. The outlet provides controls that help prevent unauthorised use of other outlets.