PDUs are required for every rack to deliver multiple outlet power ports. Every Rack in a data center must have PDU devices. The number of outlets is based on the number of servers and switches and similar devices installed in each rack. Typically this is 16-24 devices, so the most common PDU sizing is 24 outlet ports. The topic of interest recently regarding these power distribution devices is the level of intelligence required for each given customer. Some customers treat these as mechanical devices only, others expect these power devices to establish monitoring and control points at the device level. With the industry in turmoil due to the increasing cost for energy, the majority of data center operators are looking for a much more intelligent power distribution device, with deeper insight into exactly how and where energy is being used.

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