Safety And Dedicated Ground; Grounding Requirements - HP StorageWorks XP12000 Site Prep Manual

Safety and dedicated ground

The primary reason for grounding electrical systems is safety. The safety ground is
required by the National Electric Code (USA) and most other local, regional, and
national codes. In addition to safety ground, HP requires that a dedicated (earth
reference) ground be installed as a common reference point for all system components.
Consult with an HP representative and your electrician to ensure that your electrical
system meets all local and national safety codes.

Grounding requirements

Your site's electrical subsystem must meet all of the following conditions:
• Earth grounding as prescribed by your local country codes.
• An insulated grounding conductor that is identical in size and insulation material
and thickness to the ungrounded branch-circuit supply conductors. It should be
green, with or without yellow stripes, and is to be installed as a part of the
branch circuit that supplies the unit or system. This means the ground conductor
must be run in the same conduit, armored cable, or other cable bundle as the
phase wires.
• The grounding conductor should be grounded to earth at the service equipment
or other acceptable building earth ground such as the building frames (in case
of a high-rise steel-frame structure).
• IT-configured grounding systems are not certified for use with the disk array as
these grounding systems may not have solidly conductor-connected grounded
power systems and/or they may have resistive impedance inserted in ground
and/or neutral lines. The disk array requires a solidly conductor-connected
ground and may require a separate neutral in the case of WYE or STAR
connections. For HP disk arrays, TN grounding systems are preferred.
52 Site requirements