IBM SAN192C-6, Installation, Service And User Manual

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v If you are using the combined power or power-supply redundancy
mode, you can fill any power supply slot with the power supplies. If
you are using input-source or full redundancy modes, you must place
half of the power supplies in slots 1 and 2, and you must place the other
half of the power supplies in slots 3 and 4 (half will be used for available
power and the other half will be used for redundant power).
g. Screw in the two captive screws on the front of the power supply to the
chassis. Tighten each screw to 8 in-lb (0.9 N-m)
System Grounding
This section describes the need for system grounding and explains how to prevent
damage from electrostatic discharge.
Proper Grounding Practices
Grounding is one of the most important parts of equipment installation. Proper
grounding practices ensure that the buildings and the installed equipment within
them have low-impedance connections and low-voltage differentials between
chassis. When you properly ground systems during installation, you reduce or
prevent shock hazards, equipment damage due to transients, and data corruption.
Table 13 lists grounding best practices.
Table 13. Best practices
Environment
Electromagnetic Noise
Severity Level Grounding
Recommendations
Commercial building is
subjected to direct lightning
strikes.
For example, some places in
the United States, such as
Florida, are subject to more
lightning strikes than other
areas.
High All lightning protection
devices must be installed in
strict accordance with
manufacturer
recommendations.
Conductors carrying
lightning current should be
spaced away from power
and data lines in accordance
with applicable
recommendations and codes.
Appropriate grounding
practices must be closely
followed.
Commercial building is
located in an area where
lightning storms frequently
occur but is not subject to
direct lightning strikes. High Appropriate grounding
practices must be closely
followed.
Commercial building
contains a mix of information
technology equipment and
industrial equipment, such as
welding. Medium to high Appropriate grounding
practices must be closely
followed.
Chapter 3. Installing the IBM c-type SAN Device
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