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Catalyst 4500 E-Series Switches Installation Guide
OL-13972-01
Chapter 1 Product Overview
Power Supplies
Power Supply LEDs
Table 1-7 describes the power supply LEDs.
Power Supply Fan
Each power supply has a built-in fan. Air enters the front of the power supply (power-input end) and exits
through the back. An air dam keeps the airflow separate from the rest of the chassis, which is cooled by
the system fan assembly.
Load-Sharing Feature
When you install and turn on a second power supply on a Catalyst 4500 E-s eries switch, it provides
approximately one-half of the required power to the system. If o ne power supply fails, the other power
supply immediately assumes full power to maintain uninterrupted system operation.
Note Load sharing works only when both power supplies in the chassis are the same type.
Tab l e 1-7 Power Supply LEDs
LED Color/State Description
INPUT OK Indicates whether the input voltage is within the required
range:
Green Input voltage is within the required range.
Flashing Input voltage is present, but is below required range.
Off Input voltage is below the required range or the power supply
is off.
OUTPUT FAIL
Red Output voltage is not within the specified range.
Off Output voltage is within the specified range.
FAN OK Indicates the status of the power supply fans:
Green The fans are operational.
Off The fans are not operational.
In-line PWR (for
1400 W DC single
input power supplies)
Green –48 V passthru output voltage is enabled and is greater than
–39 V and less than –60 V.
Off Indicates any of the following:
• Passthru breakers are not enabled.
• DC input is less than –40.5 V.
• One or more –48 V outputs is less than –39 V.
Amber Passthru breakers are enabled and input voltage exceeds
–60 V.