Shock And Vibration Requirements; Grounding Requirements; Planning For Power Requirements - Cisco Nexus 9372PX Hardware Installation Manual

Preparing the Site
To predict and prevent strong EMI, you might need to consult experts in radio frequency interference
Note
(RFI).
The wiring is unlikely to emit radio interference if you use twisted-pair cable with a good distribution of
grounding conductors. If you exceed the recommended distances, use a high-quality twisted-pair cable with
one ground conductor for each data signal when applicable.
If the wires exceed the recommended distances, or if wires pass between buildings, give special
Caution
consideration to the effect of a lightning strike in your vicinity. The electromagnetic pulse caused by
lightning or other high-energy phenomena can easily couple enough energy into unshielded conductors
to destroy electronic switches. You might want to consult experts in electrical surge suppression and
shielding if you had similar problems in the past.

Shock and Vibration Requirements

The switch has been shock- and vibration-tested for operating ranges, handling, and earthquake standards.

Grounding Requirements

The switch is sensitive to variations in voltage supplied by the power sources. Overvoltage, undervoltage,
and transients (or spikes) can erase data from the memory or cause components to fail. To protect against
these types of problems, ensure that there is an earth-ground connection for the switch. You can connect the
grounding pad on the switch either directly to the earth-ground connection or to a fully bonded and grounded
rack.
You must provide the grounding cable to make this connection, but you can connect the grounding wire to
the switch using a grounding lug that ships with the switch. Size the grounding wire to meet local and national
installation requirements. Depending on the power supply and system, a 12-AWG to 6-AWG copper conductor
is required for U.S. installations (for those installations, we recommend that you use commercially available
6-AWG wire). The length of the grounding wire depends on the proximity of the switch to proper grounding
facilities.
You automatically ground the power supplies when you connect them to power sources. You must also
Note
connect the chassis to the facility earth ground.

Planning for Power Requirements

The switch includes two power supplies (1-to-1 redundancy with current sharing) in one of the following
combinations (all power supplies must have the same airflow direction as the fan modules):
• Two 1200-W HVAC/HVDC power supplies
Cisco Nexus 9372PX and 9372PX-E NX-OS-Mode Switches Hardware Installation Guide
Shock and Vibration Requirements
7