Electrical Power And Grounding Quality; Cooling And Humidity Control - HP Integrity NonStop X NS7 Planning Manual

Electrical Power and Grounding Quality

Proper design and installation of a power distribution system for a system requires specialized
skills, knowledge, and understanding of appropriate electrical codes and the limitations of the
power systems for computer and data processing equipment. For power and grounding
specifications, see
Power Quality
This equipment is designed to operate reliably over a wide range of voltages and frequencies,
described in
these ranges are exceeded. Severe electrical disturbances can exceed the design specifications
of the equipment. Common sources of such disturbances are:
Fluctuations occurring within the facility's distribution system
Utility service low-voltage conditions (such as sags or brownouts)
Wide and rapid variations in input voltage levels or input power frequency
Electrical storms or large inductive sources (such as motors and welders)
Faults in the distribution system wiring (such as loose connections)
To protect the system from electrical disturbances, use a dedicated power distribution system,
power conditioning equipment, and lightning arresters on power cables. For assistance, consult
with your Hewlett Packard Enterprise site preparation specialist or power engineer.
Grounding Systems
The site building must provide a power distribution safety ground/protective earth for each AC
service entrance to all system equipment. This safety grounding system must comply with local
codes and any other applicable regulations for the installation locale.
For proper grounding/protective earth connection, consult with your Hewlett Packard Enterprise
site preparation specialist or power engineer.
Power Consumption
The power consumption and inrush currents per connection can vary because of the unique
combination of enclosures housed in the rack. Calculate the total power consumption for the
hardware installed in the rack as described in

Cooling and Humidity Control

Cooling airflow through each enclosure in the system is front-to-back. Because of high heat
densities and hot spots, an accurate assessment of air flow around and through the system
equipment and specialized cooling design is essential for reliable system operation. For an airflow
assessment, consult with your Hewlett Packard Enterprise cooling consultant or your heating,
ventilation, and air conditioning (HVAC) engineer.
NOTE: Failure of site cooling with the system continuing to run can cause rapid heat buildup
and excessive temperatures within the hardware. Excessive internal temperatures can result in
full or partial system shutdown. Ensure that the site's cooling system remains fully operational
when the system is running.
Use the "NS7 Heat Dissipation Specifications and Worksheet " (page 55)
heat dissipation for the hardware installed in each rack. For air temperature levels at the site,
see "Operating Temperature, Humidity, and Altitude Specifications for NS7 Systems" (page
"Enclosure AC Input for NS7 Systems" (page
"Enclosure AC Input for NS7 Systems" (page
47).
47). However, damage can occur if
"NS7 Enclosure Power Loads" (page
Electrical Power and Grounding Quality
48).
to calculate the total
56).
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