Safety And Dedicated Ground; Grounding Requirements - HP StorageWorks XP10000 Site Preparation Manual

Safety and dedicated ground

Grounding requirements

Site requirements
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.
Your site's electrical subsystem must meet all of the following conditions:
• 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.
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