may cause problems when the power is restored; all other appliances left on in the area may create large
voltage spikes that may damage the system.
System Grounding
When installing or replacing the unit, the ground connection must always be made first and disconnected
last.
Statement 1046
Warning
Installations that rely solely on system grounding that uses only an AC third-prong ground run a
substantially greater risk of equipment problems and data corruption than those installations that use
both the AC third-prong ground and a properly installed system ground.
Caution
The following table lists some general grounding practice guidelines.
Table 3: Grounding Practice Guidelines
Grounding Recommendations
Electromagnetic Noise
Severity Level
Environment
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. Best
grounding practices must be closely
followed.
High
Commercial building is subjected to
direct lightning strikes.
For example, some places in the United
States, such as Florida, are prone to
more lightning strikes than other areas.
Best grounding practices must be closely
followed.
High
Commercial building is located in an
area where lightning storms occur
frequently, but is not prone to direct
lightning strikes.
Best grounding practices must be closely
followed.
Medium to High
Commercial building contains a mix
of information technology equipment
and industrial equipment, such as
welding.
Best grounding practices must be closely
followed. Determine source and cause of
noise if possible, and mitigate as closely as
possible at the noise source or reduce
coupling from the noise source to the
victim equipment.
Medium
Existing commercial building is not
subject to natural environmental noise
or man-made industrial noise. This
building contains a standard office
environment. This installation has a
history of malfunction due to
electromagnetic noise.
Cisco Catalyst 9200CX Compact Series Switches Hardware Installation Guide
17
Preparing for Installation
System Grounding
