Dc Power Supply Leds In Ex4500 Switches - Juniper EX4500 Hardware Manual

Each DC power supply has an ejector lever that holds the power supply in place. The ejector lever locks
into the corresponding hole in the chassis. For instructions for installing the power supply, see
a DC Power Supply in an EX4500 Switch" on page
Each power supply has its own fan and is cooled by its own internal cooling system. The airflow for a power
supply is from the front of the power supply to the back.
The color of the ejector lever on the power supply indicates the direction of airflow of the power supply.
Green—Front-to-back airflow
The color of the power supply's ejector lever must match the color of the exhaust label visible through
the vents of the installed fan tray. The color match indicates that the direction of airflow through the fan
tray matches the direction of airflow through the power supply.
CAUTION:
direction of airflow through the fan tray to prevent overheating of the chassis.
Each DC power supply provides power to all components in the switch. Two power supplies provide full
power redundancy to the switch. If one power supply fails or is removed, the second power supply balances
the electrical load without interruption. The switch reassesses the power required to support the switch
configuration and issues error messages if the available power is insufficient.
The output for the DC power supply is 12 VDC. The output power is 1200 W.
SEE ALSO
Connecting DC Power to an EX4500 Switch | 131

DC Power Supply LEDs in EX4500 Switches

A DC power supply has one bicolor LED (labeled POK) on its faceplate. This LED displays information
about the status of the power supply. See
204.
Verify that the direction of airflow through the power supply matches the
Figure 25 on page 68.
67
"Installing