S e n d d o c u m e n t c o m m e n t s t o n e x u s 7 k - d o c f e e d b a c k @ c i s c o . c o m
9-8
Cisco Nexus 7000 Series Hardware Installation and Reference Guide
OL-23069-06
Chapter 9 Replacement Procedures
Replacing a DC Power Supply Unit During Operations
Replacing a DC Power Supply Unit During Operations
The Cisco Nexus 7000 Series switches use a load-balanced power supply that uses up to three or four
AC or DC power supply units. The AC power supply units each convert up to 1.2 kW, 3 kW, 3.5 kW, 6
kW, or 7.5 kW of AC power to DC power for system operations, and the DC power supply units provide
either 3 kW or 6 kW of power for system operations. If you can set one power supply unit in standby
mode and have the required power load balanced by the remaining online power supply units, then you
can replace the standby power supply unit with another power supply unit without interrupting system
operations.
Note
If a replacement power supply unit is not available and you do not have a blank plate to cover the empty
power supply bay, you should leave the original power supply in the bay until you have the replacement
unit.
Warning
Blank faceplates and cover panels serve three important functions: they prevent exposure to
hazardous voltages and currents inside the chassis; they contain electromagnetic interference (EMI)
that might disrupt other equipment; and they direct the flow of cooling air through the chassis. Do not
operate the system unless all cards, faceplates, front covers, and rear covers are in place.
Statement 1029
This section describes how to replace a DC power supply unit and includes the following topics:
•
Removing a DC Power Supply Unit During Operations, page 9-8
•
Installing a DC Power Supply Unit During Operations, page 9-10
Removing a DC Power Supply Unit During Operations
Warning
Hazardous voltage or energy is present on the backplane when the system is operating. Use caution
when servicing.
Statement 1034
To replace a DC power supply unit while a Cisco Nexus 7000 Series switch is operating, follow these
steps:
Step 1
Make sure that the power supply units not being replaced have their power switches turned to ON.
Step 2
For the power supply unit that you are replacing, turn its power switch to STBY. The Output LED turns
off.
Step 3
Turn off the DC input power by manually turning off each input circuit at its circuit breaker.
Step 4
Verify that the input power is completely off by making sure that all of the LEDs on the DC power supply
unit are off.
Warning
Before performing any of the following procedures, ensure that power is removed from the DC circuit.
Statement 1003
Step 5
Detach each set of four DC power cables from the DC power source or DC power interface unit (PIU)
as follows:
