•
Two 1200-W NEBS-compliant AC power supplies
•
Two 1200-W standard AC power supplies
•
Two 930-W DC power supplies
•
Any combination of the above power supplies
For
n
+1 redundancy, you must provide power to both power supplies. For
n
+
n
redundancy, you must
provide power to both power supplies and each power supply must be connected to a different power
source.
Note
The power supplies are rated to output up to 1200 W (AC, NEBS-compliant AC, and HVAC/HVDC power
supplies) or up to 930 W (DC power supplies), 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 400 W of power input from the power source, but you must provision as much as 660 W power input
from the power source to cover peak demand.
To minimize the possibility of circuit failure, make sure that each power-source circuit used by the switch is
dedicated to the switch.
For the AC power cables that you can use with this switch, see
Power Cord Specifications, on page 47
.
For DC power cables, the recommended wire gauge is 8 AWG and the minimum wire gauge is 10 AWG.
Note
Airflow Requirements
The switch is designed to be positioned with its ports in either the front or the rear of the rack depending on
your cabling and maintenance requirements. Depending on which side of the switch faces the cold aisle, 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
—
Coolant air enters the chassis through the fan and power supply modules in
the cold aisle and exhausts through the port end of the chassis in the hot aisle.
•
Port-side intake airflow
—
Coolant air enters the chassis through the port end in the cold aisle and exhausts
through the fan and power supply modules in the hot aisle.
•
Dual-directional airflow
—
The airflow direction of the power supplies is determined by the airflow
direction of the fan modules.
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.
•
Gray coloring on DC power supplies indicates port-side exhaust airflow.
•
Green coloring on DC power supplies indicates port-side intake airflow.
Cisco Nexus 9336PQ ACI-Mode Switch Hardware Installation Guide
8
Preparing the Site
Airflow Requirements
