Removing the T640 Power Supplies

The power supplies are located at the rear of the chassis below the SIBs. Each two-input 160-A DC power supply weighs approximately 23 lb (10.5 kg). Each three-input 240-A DC power supply weighs approximately 25 lb (11.3 kg). Each four-input 240-A DC power supply weighs approximately 26.6 lb (12.0 kg). Each AC power supply weighs 31.0 lb (14.06 kg).

To remove the power supplies, starting with the upper power supply:

1. Attach an electrostatic discharge (ESD) grounding strap to your bare wrist, and connect the strap to an approved site ESD grounding point. See the instructions for your site.
2. Switch the circuit breakers on the DC power supply faceplates to the off position (O) or the power switches on the AC power supply faceplates to the standby position. We recommend this even though the power supplies are not connected to power sources.
3. Loosen the captive screws on the lower corners of the power supply faceplate completely.
4. Twist the ejector handles on the upper corners of the faceplate counterclockwise to unseat the power supply.
5. Grasp the handle on the power supply faceplate and pull firmly to start removing the power supply. Slide it halfway out of the chassis (see Figure 1).

   Caution: Be prepared to support the full weight of the power supply as you remove it from the router.

6. Place one hand underneath the power supply to support it and slide it completely out of the chassis.
7. Repeat the procedure for the other power supply.

Note: Figure 1 shows the two-input 160-A DC power supply, but the procedure also applies to the three-input 240-A DC power supply.

Figure 1: Removing a Power Supply Before Installing the Router