Site Preparation Guide, Second Edition - HP Integrity cx2620 Server

3. Check that the braid contact connection points are free of paint or other insulating material
and treated with a contact enhancement compound (similar to Burndy Penetrox).
4. Attach the other end to the nearest pedestal base (raised floor) or cable trough ground point
(nonraised floor).
5. After achieving a safe and effective 50–60Hz grounding system and a safe and effective SRG,
then consider cabinet-to-floor grounding. HP does not require this step.
System Installation Guidelines
This section contains information about installation practices and highlights some common
installation pitfalls. It addresses both power cable and data communications cable installations,
and highlights installation.
NOTE: In domestic installations, the proper receptacles should be installed prior to the arrival
of HP equipment. Refer to the appropriate installation guide for installation procedures.
Wiring Connections
Expansion and contraction rates vary among different metals. Therefore, the integrity of an
electrical connection depends on the restraining force applied. Connections that are too tight
compress or deform the hardware and cause it to weaken. This usually leads to high impedance,
preventing circuit breakers from tripping when needed, or can contribute to a buildup of high
frequency noise.
CAUTION: Connections that are too loose or too tight can have a high impedance that causes
serious problems, such as erratic equipment operation. A high impedance connection overheats
and sometimes causes fire or high temperatures that can destroy hard-to-replace components
such as distribution panels or system bus bars.
Wiring connections must be properly torqued. Many equipment manufacturers specify the proper
connection torque values for their hardware.
Ground connections must only be made on a conductive, nonpainted surface. When equipment
vibration is present, lock washers must be used on all connections to prevent connection hardware
from working loose.
Data Communications Cables
Power transformers create high-energy fields in the form of electromagnetic interference (EMI).
Heavy foot traffic can create electrostatic discharge (ESD) that can damage electronic components.
Route data communications cables away from these areas. Use shielded data communications
cables that meet approved industry standards to reduce the effects of external fields.
Environmental Elements
Synopsis
Air Quality
Proper computer room preparation improves air quality. It provides a return on investment by
making a system more stable and by decreasing unexpected downtime. HP recommends putting
appropriate effort into maximizing electrical and air conditioning efficiency to ensure higher
reliability to meet business needs.
HP temperature and humidity recommendations follow newly established industry standards.
HP recommends the following operating ranges:
• Temperature of 20–25°C (68–77°F)
• Humidity of 40–55 percent relative humidity
Environmental Elements 29