System Installation Guidelines; Wiring Connections; Data Communications Cables; Environmental Elements - HP Rp3440-4 - 9000 - 0 MB RAM Manual

2. Check that the braid contact on each end of the ground strap consists of a terminal and
connection hardware (a 1/4-inch (6.0-mm) bolt, nuts, and washers).
3. Attach one end of each ground strap to the applicable cabinet ground lug.
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 hazards. It addresses both power and data communications cable installations, and
highlights installation.
NOTE:
In domestic installations, install approved receptacles before the HP equipment arrives.
See 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. High impedance can also contribute to
a buildup of high-frequency noise.
CAUTION:
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. See the safety requirements provided by your wire
manufacturer.
Ground connections must be made only 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) which can damage electronic
components. Route data communications cables away from these areas and use shielded data
communications cables that meet approved industry standards to reduce the effects of external
energy 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.
Connections that are too loose or tight can have a high impedance which cause
Environmental Elements 15