How to choose a PDU for a rack cabinet

Power supply in a rack may seem simple until the time comes to connect multiple pieces of equipment. Servers, switches, and other devices may require different outlets, different cable routes, and space for maintenance. A PDU helps distribute connections inside the cabinet, but choosing one only by the number of outlets can leave important aspects unchecked.

What is a PDU for a rack?

A PDU (power distribution unit) is a device with several electrical outlets intended to power equipment installed in the rack. In compact formats, it may appear as a 19-inch power strip mounted on the cabinet profiles. Its specific function depends on the model: some are basic distribution strips; others may include additional functions. For this reason, it is advisable to read the technical data sheet before assuming measurement, remote control, or electrical protection capabilities.

The rack may be in a communications room, a network installation, or a data center. In all these cases, the PDU is selected in relation to the equipment to be connected and the available power supply. Two cabinets of the same size may require very different power distributions.

Five checks before choosing one

1. Make an inventory of the equipment. Note how many connections are needed today and which ones could be added in the short term. Leave spare outlets, but do not confuse the number of outlets with the power that can be delivered.
2. Check the connectors. Review the plug type of each device and the PDU input type. An available outlet is no use if the connector is not compatible.
3. Calculate the expected load. Check the consumption of the equipment and the limits stated in the PDU data sheet. Also review the circuit supplying it. If the installation requires redundancy, plan both power paths with the responsible technical staff.
4. Verify mounting and space. Confirm the fixing format, the height units it occupies, and access to the outlets. Take cable length into account and avoid connections that hinder airflow or maintenance.
5. Assess the use of the switch. In some environments it may be practical; in others, accidental shutdown is best avoided. The decision must fit the rack operating procedure.

Schuko, IEC C13 or IEC C19: what do you need?

The outlet type must match the plug of each device. In the same project, there may be devices with Schuko connectors and others requiring IEC C13 or C19 outlets. That is why a list of equipment with the connector type and the number of required outlets helps avoid choosing a strip that, despite having enough outlets, does not allow all devices to be connected.

In addition to counting outlets, it is advisable to map where the equipment will be located. The position of the outlets and the input cable affects cable routing and access during maintenance. If you are considering a vertical PDU or a horizontal 19-inch power strip, check how it will be mounted in the specific cabinet and how much space it will occupy. The appropriate configuration depends on the project, not only on a preference for one format.

Immediate-delivery models and other configurations

On the Citadex website there are two 19-inch rack PDUs with immediate delivery: the 8-outlet Schuko strip with switch and safety cover and the 9-outlet Schuko strip without switch. Both data sheets describe them as 1U devices, with a 1.8-meter cable and a stated maximum power of 3,500 W. These figures apply only to these models.

Citadex can also offer other PDU configurations on request, with more Schuko outlets, different outlet types such as IEC C13 or C19, and smart PDU options, depending on project requirements. Check with the team the layout, features, price, and lead time for the configuration you need.

In a smart PDU, functions may vary depending on the model and configuration. If you need to monitor consumption, receive electrical status information, or manage outlets remotely, specify exactly what you want to do when requesting information. This makes it possible to assess an option that includes the necessary functions, without assuming that all smart PDUs do the same thing.

What to send us to assess your PDU

An inquiry can start with four data points: the list of equipment, the number and type of outlets required, the available power supply, and the rack model or dimensions. If you have a distribution layout or know where you want to install the PDU, attach it. Also indicate whether you need smart functions and which ones, as well as the expected project timeline.

With that information, it is easier to determine whether one of the immediate-delivery models fits or whether a different configuration should be proposed. Before installation, the responsible technical staff must verify that the PDU, the equipment, and the electrical circuit are compatible.

The PDU determines how the equipment is connected, identified, and maintained. If you are configuring or expanding a rack, check the published models or ask Citadex about a different configuration. Indicate how many devices you will connect, which outlets they require, and which functions you need so that we can inform you of the available options.