Installing a DC Power Supply
This topic is for installing the 48-V DC power supply into switch chassis. If you need to install a high voltage
(HVAC/HVDC) power supply, see
Installing an HVAC/HVDC Power Supply, on page 42
.
You can replace one power supply while the other one provides power to the switch.
Before You Begin
•
The circuit breaker for the DC power source for the power supply must be turned off.
•
The power supply that you are installing must be capable of using the same airflow direction as the fan
trays installed in the same switch
•
A DC power source must be within reach of the power cable that will be used with the replacement
power supply. If you are using
n
+
n
power redundancy, there must be a separate power source for each
power supply installed in the chassis (do not mix AC and DC power sources for the same switch).
Otherwise, only one power source is required.
•
There must be an earth ground connection to the chassis that you are installing the replacement module.
Typically, the chassis is grounded by its metal-to-metal connection to a grounded rack. If you need to
ground this chassis by another means, see
Grounding the Chassis, on page 27
.
Step 1
Holding the replacement power supply with one hand underneath the module and the other hand holding the handle, turn
the power supply so that its release latch is on the right side and align the back end of the power supply (the end with
the electrical connections) to the open power supply slot before carefully sliding the power supply all the way into the
slot until it clicks into place.
If the power supply does not fit into the open slot, turn the module over before carefully sliding it into the open
slot.
Note
Step 2
If the DC power cables and a grounding cable are already connected to an electrical connector block, insert the block
into the power receptacle on the power supply.
If the electrical cables have not been connected to the electrical connector block, wire them as described in
V DC Electrical Connector Block, on page 43
.
Step 3
Turn on the circuit breaker for the DC power source connected to the power supply.
Step 4
Verify that the power supply is operational by making sure that the power supply
LED is green. For information on
what the power supply LEDs indicate, see
Power Supply LEDs, on page 58
.
Wiring a 48 V DC Electrical Connector Block
You must connect the ground, negative, and positive DC power cables to a connector block in order to connect
the power cables to a 48 V DC power supply.
The recommended wire gauge is 8 AWG. The minimum wire gauge is 10 AWG.
Note
Cisco Nexus 9396PX NX-OS Mode Switch Hardware Installation Guide
43
Replacing Modules
Installing a DC Power Supply
