11-8
Software Configuration Guide—Release 15.0(2)SG
OL-23818-01
Chapter 11 Configuring Power over Ethernet
Displaying the PoE Consumed by a Module
Displaying the PoE Consumed by a Module
A Catalyst 4500 series switch can measure the actual PoE consumption for an 802.3af-compliant PoE
module. You can observe this consumption by using show power module and show power detail
commands. For all PoE calculations, presume that the PoE consumption on the WS-X4148-RJ45V
module equals its administrative PoE.
The 802.3af-compliant PoE modules can consume up to 20 W of PoE to power FPGAs and other
hardware components on the module. To ensure that the system has sufficient power for the PDs
connected to the switch, add at least 20 W to your PoE requirements for each 802.3af-compliant PoE
module.
The following example uses the show power module command to display the PoE consumption for an
802.3af-compliant module:
Switch# show power module
Watts Used of System Power (12V)
Mod Model currently out of reset in reset
---- ----------------- --------- ------------ --------
1 WS-X4013+TS 330 330 330
2 WS-X4548-GB-RJ45V 60 60 20
3 WS-X4548-GB-RJ45V 60 60 20
-- Fan Tray 30 -- --
----------------------- --------- ------------ -------
Total 480 450 370
Watts used of Chassis Inline Power (-50V)
Inline Power Admin Inline Power Oper
Mod Model PS Device PS Device Efficiency
---- ----------------- ---------------- ---------------- ----------
2 WS-X4548-GB-RJ45V 138 123 73 65 89
3 WS-X4548-GB-RJ45V 0 0 22 20 89
----------------------- ---------------- ---------------- ----------
Total 138 123 95 85
Watts used of Module Inline Power (12V -> -50V)
Inline Power Admin Inline Power Oper
Mod Model PS Device PS Device Efficiency
---- ----------------- ---------------- ---------------- ----------
1 WS-X4013+TS 128 128 63 63 100
----------------------- ---------------- ---------------- ----------
Switch#
The Inline Power Oper column displays the amount of PoE consumed by the powered devices that are
attached to the module, in addition to the PoE consumed by the FPGAs and other hardware components
on the module.
The Inline Power Admin column displays only the amount of PoE allocated by the powered devices
attached to the module.
Note The operating PoE consumption for an 802.3af-compliant module can be non-zero, even when no
powered devices are attached to the module, because of the PoE consumed by FPGAs and other hardware
components on the module. In addition, the operating PoE can vary because of fluctuations in the PoE
consumed by the hardware components.