To begin, power distribution units are devices fitted with many outlets to distribute power to servers, storage devices, and network equipment located within racks in a data center.  Stable, reliable power is part of the base expectations for a PDU.  PDUs can be intelligent, with an array of options to choose from, or non-intelligent for a lower cost and faster setup. 

PDUs provide continuous power to the equipment it is supporting, offering simple power distribution and branch circuit protection to the critical devices.  Power can be switched on and off, but there are more features for consideration.  Environmental sensors, monitoring and metering the branch circuits, and level of accuracy are important additions to PDUs. 

Start with what you need; one of the biggest mistakes is getting a PDU that isn’t as capable as what is needed.  Determining the power requirements and capabilities for a particular application.  There are a wide variety of solutions with defaults to include features for surge suppression, remote and/or local monitoring, remote booting and more.  While a lot of the features are useful for certain customers, they can add unnecessary cost and complexity if they won’t be utilized. 

By using three-phase power instead of single phase the breaker density at the panel and power density at the rack will give the data center more flexibility to grow with its new needs.  Working with what is needed on the power supply can offer more options from power installed at the rack. 

Cable management and circuit locations are other considerations for those working in the data center.  It can impact air flow and therefore thermal dissipation, and the use of multiple circuits is aimed to improve the redundancy and decrease the possibility of overload.