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28-4
Catalyst 4500 Series, Catalyst 2948G, Catalyst 2948G-GE-TX, and Catalyst 2980G Switches Software Configuration Guide
—
Release 8.2GLX
78-15908-01
Chapter 28 Power Management
Understanding How Power Management Works on the Catalyst 4500 Series Switches
Available Power for Power Supplies
Table 28-1
lists the power that is provided by the power supplies for the Catalyst 4500 series switches.
Power Management Limitations
This section describes the power-management limitations for the Catalyst 4500 series switches.
Note
To compute the power requirements and verify that your system has enough power, add the power that
is consumed by the supervisor engine(s), the fan trays, and the installed modules (including the PoE).
For more information, see the
“Power Consumption for Modules” section on page 28-9
.
•
You can set the power requirements for the installed modules to exceed the power that is provided
by the power supplies.
•
If you insert a single power supply into the switch and then set combined mode, the switch displays
this message:
Insufficient power supplies present for specified configuration.
Table 28-1 Available Power
Power Supply
Redundant Mode (W)
Combined Mode (W)
1000 W AC
Chassis
1
= 1000
PoE = 0
1.
The chassis power includes power for the supervisor engine(s), all line cards, and the fan tray.
Chassis = 1667
PoE = 0
1300 W AC
2
2.
The backplane consumes 10 W in both redundant and combined mode.
Chassis (max) = 1000
PoE (max) = 800
C PoE + backplane < 1300
Chassis (min) = 767
Chassis (max) = 1667
PoE (min) = 433
PoE (max) = 1333
C PoE + backplane < 2166
1400 W DC
3
3.
The backplane consumes 10 W in redundant mode.
Chassis (min) = 200
Chassis (max) = 1360
PoE (max)
4
= (DC input
5
−
[Chassis (min) + backplane] / 0.75) *
0.96
4.
The 1400 W DC power supply has 0.75 efficiency. PoE has 0.96 efficiency.
5.
The DC input can vary for the 1400 W DC power supply and is configurable. For more information, see the
“Power
Management Limitations” section on page 28-4
.
N/A
2800 W AC
Chassis = 1360
PoE = 1400
Chassis = 2473
PoE = 2545