Cisco Nexus 93120TX Hardware Installation Manual page 18

Planning for Power Requirements
Note For n+1 redundancy, you can use one or two power sources for the two power supplies. For n+n redundancy,
you must use two power sources and connect each power supply to a separate power source.
The power supplies are rated to output up to either 1200 W (AC and HVAC/HVDC power supplies) or 930
W (DC power supplies) to the switch, but the switch requires less than those amounts of power from the power
supply. To operate the switch, you must provision enough power from the power source to cover the
requirements of both the switch and a power supply. Typically, this switch and a power supply require about
542 W of power input from the power source, but you must provision as much as 948 W power input from
the power source to cover peak demand.
Note
Some of the power supply modules have rating capabilities that exceed the switch requirements. When
calculating your power requirements, use the switch requirements to determine the amount of power that is
required for the power supplies.
To minimize the possibility of circuit failure, make sure that each power-source circuit that is used by the
switch is dedicated to the switch.
Note
For AC input application, please refer to the following statement:
Warning
Statement 1005 Circuit Breaker
This product relies on the building's installation for short-circuit (overcurrent) protection. Ensure that the
protective devices are rated not greater than 20A (North America), 16A (Europe), and 13A (UK).
Note For DC input application, please refer to the following statement:
Warning
Statement 1005 Circuit Breaker
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).
Cisco Nexus 93120TX NX-OS Mode Switch Hardware Installation Guide
8
Preparing the Site