Site Preparation Guide, Second Edition - HP Integrity cx2620 Server

• Neutral and ground wires have specific uses. Do not interchange them.
• Do not use conduit grounds in place of a separate grounding conductor to each receptacle.
• Size ground wires to be equal to the power source wires.
• Do not daisy chain phase, neutral, and ground wires.
• If the system is on raised flooring, use a 2-foot x 2-foot (61-cm x 61-cm) grounding grid.
Comprehensive Discussion
IMPORTANT: Electrical practices and suggestions in this guide are based on North American
practices. For regions and areas outside North America, local electrical codes will take precedence
over North American electrical codes.
An example would be the recommendation that the PE (Protective Earthing) conductor be green
with yellow stripes. This requirement is a North American directive and does not override the
local code requirements for a region or area outside North America.
Local Authority Has Jurisdiction (LAHJ) and should make the final decision regarding adherence
to region-specific or area-specific electrical codes and guidelines.
Proper design and installation of a power distribution system requires specialized skills. Those
responsible for this task must have a thorough knowledge and understanding of appropriate
electrical codes and the limitations of the power systems for computer and data processing
equipment.
In general, 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 information. However, electrical factors relating to power distribution system design and
installation must be considered during the site preparation process.
The electrical factors discussed in this section are:
• Computer room safety
• Power consumption
• Electrical load requirements (circuit breaker sizing)
• Power quality
• Distribution hardware
• System installation guidelines
Computer Room Safety
WARNING! The safety of personnel must be paramount in consideration of performing the
following recommendations. Failure to comply can create life-threatening scenarios.
Inside the computer room, fire protection and adequate lighting (for equipment servicing) are
important safety considerations. Federal and local safety codes govern computer installations.
Fire Protection
The National Fire Protection Association’s Standard for the Protection of Electronic Computer
Data Processing Equipment, NFPA 75, contains information on safety monitoring equipment
for computer rooms.
Electrical Factors 23