Cisco Catalyst 4900 Series Installation Manual page 72

Identifying Startup Problems
Table 5-1
LED and Color
INPUT OK (AC)
Green
Red
Off
INPUT OK (DC)
Green
Red
Off
OUTPUT OK
Green
Red
Verify that the LEDs on the front panel are lit:
Step 2
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Catalyst 4900 Series Switch Installation Guide
5-4
Power Supply LED Meanings
Meaning
This LED should turn green immediately when power is
applied to the supply and the power switch is set to ON.
AC input voltage is greater than 82 +/-3V.
In a dual power supply configuration (alternate unit
powered) the AC input is less than 73 +/-3V, or the power
supply is turned off.
AC input voltage is less than 73 +/-3V, or the power supply
is turned off.
This LED should turn green immediately when power is
applied to the supply.
DC input voltage is greater than -38.25 +/-2.25V.
In a dual power supply configuration (alternate unit
powered) the DC input is less than 33 +/-3V, or the power
supply is turned off.
In a single supply configuration, the LED shall be off to
signal that DC input is less than 33 +/-3V, or the power
supply is turned off.
DC output voltages are within the normal operating range.
Output voltage between the minimum and maximum limits
will not create an output fail alarm. Output voltages below
the minimum or above the maximum will create an output
fail alarm and cause the LED to illuminate red.
The STATUS LED flashes yellow during diagnostic boot tests. It is green
when the switch is operational (online). If the system software is unable to
start up, this LED stays orange.
Chapter 5 Troubleshooting the Installation
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