Cisco 4124 Benutzerhandbuch

When you install a redundant power supply, load sharing and fault tolerance are 
enabled automatically; no additional software configuration is required.

With the environmental monitoring and reporting feature, you can keep your 
system running by resolving adverse environmental conditions before loss of 
operation. The power supply monitors its own internal temperature and voltages. 
In the event of excessive internal temperature, the power supply shuts down to 
prevent damage. When the power supply returns to a safe operating temperature, 
it restarts. If the power supply output voltage is abnormal, the LED labeled 
OUTPUT FAIL will light. An instance of substantial input overvoltage can shut 
down the power supply. 

The supervisor engine monitors the status of each power supply and provides a 
status report through the switch software. For more information on how the 
supervisor engine monitors the power supplies, refer to the Catalyst 4500 Series 
Module Installation Guide.

The Catalyst 4006 external power shelf contains up to three single-phase, AC-DC, 
1050 W, –52 V output power supplies, which can provide Power over Ethernet to 
enabled switching modules when used with the power entry module.