Three-phase power considerations for racks
Increasing power requirements for racks are making the use of three-phase power at the rack
level compelling.
■
With single-phase power, at any given time the voltage across the hot and neutral
conductors can be anywhere between its peak (maximum) and zero. Electrical conductors
must be large to meet high amperage requirements.
■
Three-phase power uses three cycles that are 120 degrees out of phase, which never
allows the voltage to drop to zero. The more consistent voltage derived from the three hot
conductors results in smoother current flow and allows small-gauge conductors to be used
to distribute the same amount of AC power. As a result, the load balancing and increased
power handling capabilities of three-phase distribution can result in more efficient and less
costly installations that require fewer AC cables and PDUs.
Cable management
Rack installations should be planned for operational efficiency, ease of maintenance, and
safety. Hitachi offers the Backend Configuration Utility (BECK), a graphical, cable-
management application that can relieve the typical cable congestion created when
populating a rack with storage systems and their accessories.
Three-phase power considerations for racks
Appendix F: Data and power cables
VSP N400, N600 Hardware Reference Guide
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