12-13
Software Configuration Guide—Release IOS XE 3.3.0SG and IOS 15.1(1)SG
OL-25340-01
Chapter 12 Environmental Monitoring and Power Management
Power Management
• For variable power supplies, choose a power supply that provides enough power so that the chassis
and PoE requirements are less than the maximum available power. Variable power supplies
automatically adjust the power resources at startup to accommodate the chassis and PoE
requirements.
• If you have the power management mode set to combined mode and only one power supply installed,
your switch accepts the configuration, but power is available from only one power supply.
• When your switch is configured to combined mode, the total available power is not the mathematical
sum of the individual power supplies. The power supplies have a predetermined current sharing ratio
See Table 12-5 on page 12-14 for more information.
• The maximum available power for chassis and PoE for each power supply are listed in Table 12-5
on page 12-14.
To configure combined mode on your Catalyst 4500 series switch, perform this task:
The following example shows how to set the power management mode to combined mode:
Switch(config)# power redundancy-mode combined
Switch(config)# end
Switch#
The following example shows how to display the current power redundancy mode. The power supplies
needed by system: 2 indicates that the switch is in combined mode.
Switch# show power supplies
Power supplies needed by system:2
Switch#
Available Power for Catalyst 4500 Series Switches Power Supplies
Table 12-5 lists the power available for use in the various Catalyst 4500 series switches power supplies.
When your switch is configured to combined mode, the total available power in not the mathematical
sum of the individual power supplies. The power supplies have a sharing ratio predetermined by the
hardware. In combined mode, the total power available is P + (P * sharing-ratio), where P is the amount
of power in the power supply.
Command Purpose
Step 1
Switch# configure terminal Enters configuration mode.
Step 2
Switch(config)# power redundancy-mode combined Sets the power management mode to
combined mode.
Step 3
Switch(config)# end
Exits configuration mode.
Step 4
Switch# show power supplies Verifies the power redundancy mode for
the switch.