Preparing the Site
Warning
Warning
Note
Note
Airflow Requirements
The switch is positioned with its ports in either the front or the rear of the rack depending on your cabling
and maintenance requirements. You must have fan and power supply modules that move the coolant air from
the cold aisle to the hot aisle in one of the following ways:
• Port-side exhaust airflow—Cool air enters the chassis through the fan and power supply modules in the
• Port-side intake airflow—Cool air enters the chassis through the port end in the cold aisle and exhausts
You can identify the airflow direction of each fan and power supply module by its coloring as follows:
• Blue coloring indicates port-side exhaust airflow.
• Burgundy coloring indicates port-side intake airflow.
• White coloring on HVAC/HVDC power supplies indicates dual-direction airflow.
• Gray coloring on DC power supplies indicates port-side exhaust airflow.
• Green coloring on DC power supplies indicates port-side intake airflow.
Statement 1005 Circuit Breaker when using DC power supplies
This product relies on the building's installation for short-circuit (overcurrent) protection.
• Ensure that the protective devices are rated not greater than 30A when the switch is powered with regular
DC power supplies (rated 48-60VDC).
• Ensure that the protective devices are rated not greater than 10A when the switch is powered with HVDC
power supplies (rated 240-350VDC).
Statement 1033
Connect the unit only to DC power source that complies with the Safety Extra-Low Voltage (SELV)
requirements in IEC 60950 based safety standards.
We recommend 8-AWG wire for DC installations in the U.S.
For the power cables to use with the power supplies, see
cold aisle and exhausts through the port end of the chassis in the hot aisle.
through the fan and power supply modules in the hot aisle.
Power Cable Specifications, on page
Cisco Nexus 9396TX ACI-Mode Switch Hardware Installation Guide
Airflow Requirements
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