Installation Guide

Replacing a Summit 450 W or 550 W DC Power Supply
Summit 550 W power supply units (PSUs) are available with either front-to-back or back-to-front
airflow. If you install two PSUs, both must have the same airflow direction.
Note
You cannot combine power supplies of dierent wattages in the same switch.
You need the following tools and materials to replace a 450 W or 550 W DC power supply:
• #1 Phillips screwdriver
• Torque screwdriver and wrench or torque driver with attachments for tightening screws and nuts
• Thermal protective gloves (required for removal of a power supply)
Removing a 450 W or 550 W DC Power Supply
To remove an installed 450 W or 550 W DC power supply, follow these steps:
Caution
The DC power supply may be hot to the touch; use thermal protective gloves when handling
the power supply during removal.
1. De-energize the DC circuit.
2. Disconnect the DC power cables:
a. Pull the cover o the terminal block.
b. Loosen the screws that secure the cable terminals to the terminal block.
c. Slide the wires out from under the captive washers.
Warning
Be sure to disconnect all power cables before you disconnect the chassis ground wire.
3. Disconnect the ground wire as follows:
a. Loosen the screw that secures the ground wire to the terminal block.
b. Slide the wire out from under the captive washer.
4. Note the orientation of the installed power supply.
Replacing DC Power Supplies
Replacing a Summit 450 W or 550 W DC Power Supply
ExtremeSwitching Hardware Installation Guide 353