Power requirements and considerations

Power requirements

When planning power distribution requirements, observe the following:

•The power load must be balanced between available AC supply branch circuits.

•The AC current load attached to a branch circuit must not exceed 80 percent of that branch circuit current rating.

•If a UPS system is used, when the peak load reaches 90 percent of the non-redundant UPS system capacity, no new loads can be installed until the UPS system capacity is increased.

Installation of this equipment must be performed by licensed electricians and must comply with local and regional electrical regulations governing the installation of IT equipment. This equipment is designed to operate in installations covered by NFPA-70 (National Electric Code) and NFPA-75 (code for Protection of Electronic Computer/Data Processing Equipment). For electrical power ratings on options, refer to the product rating label or the user documentation supplied with that option

WARNING: To reduce the risk of personal injury, fire, or damage to the equipment, do not overload the AC supply branch circuit that provides power to the rack. Consult the electrical authority having jurisdiction over wiring and installation requirements of your facility.

CAUTION: Protect the enclosure from power fluctuations and temporary interruptions with a regulating UPS. This device protects the hardware from damage caused by power surges and voltage spikes and keeps the enclosure in operation during a power failure.

Electrical factors

Proper design and installation of a server power distribution system requires specialized skills. Those responsible for this task must have a thorough knowledge of appropriate electrical codes and the limitations of the power systems for computer and data processing equipment.

A well designed power distribution system exceeds the requirements of most electrical codes. A good design, when coupled with proper installation practices, produces the most trouble-free operation.

A detailed discussion of power distribution system design and installation is beyond the scope of this document. However, electrical factors relating to power distribution system design and installation must be considered during the site preparation process.

IMPORTANT: Electrical practices and suggestions in this guide are based on North America practices. For regions and areas outside North America, local electrical codes take precedence over North American electrical codes.

Local authority has jurisdiction (LAHJ) and should make the final decision regarding adherence to region-specific or area-specific electrical codes and guidelines.

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