User's Manual

1-8
Cisco Catalyst 4900M S witch Inst allati on Guide
78-18350- 0 2
Chapter 1 Product Overview
Catalyst 4900M Half-Card Modules
For safety reasons , the AC power supp ly must be swi tched off a nd unplug ged befo re it i s removed from
a chassis or inserted into a chassis. DC supplies should have power shut off from the source before they
are removed.
If only one power supply is used, you m ust use the supplied blank face plate to cover the empty power
bay. The blank power supply cover mainta ins EMI shielding and prope r air flow through the chassi s.
Environmental Monitoring of the Po wer Supplies
Using the environmental monitoring and reporting functions, you can maintain normal system operation
by resolving adverse environmental conditions prior to loss o f operation.
Each power supply monitors its own temper ature and output voltages. The Catalyst 4900 M switch sen ses
the operating condition of the power supply and reports status through software.
Power Managem ent for t he Cata lyst 4900M Switch
You can select either AC-input or DC-input p ower supplie s for your switch. Th e Cata lyst 4900M switc h
supports the following power suppl ies:
• 1000 W AC-input
• 1000 W DC-input
A redundant power supply can be iden tified and diagnosed by a runn ing system regardles s of its input
status. The AC-input and DC-input supplies are interc hangeable.
Power Management Modes
The Catalyst 4900M switch supports the redundant pow er management mode. In this m ode, if both
power supplies are operatin g normally, each provides fro m 20/80 to 45/55 percent of the total system
power requirements at all times. If one power supply fails, the other unit increases power to 100 percent
of the total power requirement.
Catalyst 4900M Half-Card Modules
The Catalyst 4900M switch chassis has two half-card slots available allow ing two half-card modules to
be installed. The following ha lf-card modules are availa ble:
• WS-X4920-GB-RJ45 Half- Card Ethernet Modul e, page 1-9
• WS-X4904-10GE Half-Car d Ethernet Module, pa ge 1-10
• WS-X4908-10GE Half-Car d Ethernet Module, pa ge 1-11
• WS-X4908-10G-RJ45 H alf-Car d Etherne t Module, pa ge 1-1 3
The half-card modules can be mixed i n a chassis.