Remove a DC Power Supply

The DC power supplies are located at the bottom rear of the chassis (see Figure 2). Each DC power supply weighs approximately 20 lb (9 kg).

Do not leave a power supply slot empty for more than a short time while the router is operational. The power supply must remain in the chassis for proper airflow.

To remove a DC power supply, follow this procedure:

1. Turn off the power flowing from the DC power source to the power supply. Ensure that the voltage across the leads of the DC power cables that you are disconnecting is 0 V and that there is no chance that the cable leads might become active during removal.
2. Attach an ESD strap to your bare wrist and connect the strap to one of the ESD points on the chassis.
3. Flip the power switch on the power supply faceplate to the OFF (O) position.  See Figure 55
   
   

   If you are not removing the power supply, but simply powering it off, wait at least 60 seconds before turning it back on. If you need to power it off again, wait for at least 60 seconds after powering it on.

   
   

Figure 55: Flip the Power Switch on a DC Power Supply to the OFF Position

4. Using a Phillips screwdriver, loosen the screws securing the protective shield over the power terminal studs and remove the shield. See Figure 56.

Figure 56: Remove the Protective Shield from the Terminal Studs

5. Using a 7/16-in. nut driver or wrench, loosen the nuts that secure the power cable lugs to the terminal studs. Remove the nuts, washers, and lug from each set of terminal studs. See Figure 57.  
   
   

   Do not substitute a metric nut driver or wrench. A tool that does not fit the nuts exactly can damage them. If a 7/16-in. tool is not available, use pliers or an adjustable wrench.

   
   
6. Using a 7/16-in. nut driver or wrench, loosen the nuts that secure the grounding cable lug to the grounding studs. Remove the nuts, washers, and lug from the grounding studs.

Figure 57: Remove Cables from a DC Power Supply

7. Loosen the thumbscrew at each upper corner of the power supply faceplate, using a Phillips screwdriver if necessary.
8. Lift and hold up the safety interlock lever, which is just below the power switch.
9. While holding the safety interlock lever up, turn the extractor/inserter counterclockwise until the power supply disengages from the backplane. See Figure 58.
10. Grasp the handle on the power supply faceplate and pull firmly to slide the unit about halfway out of the chassis.
11. Place one hand under the power supply to support it, then slide it completely out of the chassis.

Figure 58: Remove a DC Power Supply