System Grounding; Proper Grounding Practices - Cisco MDS 9700 Series Installing

Installing the Cisco MDS 9700 Series Switches
Note
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.
practices.
Table 1: Grounding Best Practices
Environment
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.
Commercial building is located in an area
where lightning storms frequently occur but
is not subject to direct lightning strikes.
Commercial building contains a mix of
information technology equipment and
industrial equipment, such as welding.
The lever should grab the inside of the slot and push the power supply onto its mid-plane connectors.
• 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).
• In a single phase AC power supply unit, connection of multiple phases from the same three-phase
source is supported and direct connection of three-phase is not supported.
Electromagnetic Grounding Recommendations
Noise Severity
Level
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.
High Appropriate grounding practices must be
closely followed.
Medium to Appropriate grounding practices must be
high closely followed.
Installing the Cisco MDS 9700 Series Switches
System Grounding
Table 3-1 lists grounding best
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