Replacing a T640 Three-Phase Wye AC Power Supply

1. Removing a T640 Three-Phase Wye AC Power Supply
2. Installing a T640 Three-Phase Wye AC Power Supply

Removing a T640 Three-Phase Wye AC Power Supply

1. Switch off the customer site circuit breakers to the power supply being removed. Make sure that the voltage across the AC power source cord is 0 V and that there is no chance that the power cord might become active during the removal process.
2. Attach an electrostatic discharge (ESD) grounding strap to your bare wrist, and connect the strap to one of the ESD points on the chassis.
3. Switch the power switch on the power supply faceplate to the standby position.

   Note: After powering off a power supply, wait at least 60 seconds before turning it back on.

4. Remove the ESD grounding strap from the ESD point on the chassis, and attach it to an approved site ESD grounding point. See the instructions for your site.
5. Disconnect the AC power cord (see Figure 1) from the power source.

   Figure 1: Three-Phase Wye AC Power Supply

   
6. Remove the ESD grounding strap from the approved site ESD grounding point. See the instructions for your site. Reconnect the strap to one of the ESD points on the chassis.
7. Using a number 2 Phillips (+) screwdriver, unscrew the two screws on the metal cover protecting the AC terminal block.

8. Disconnect the wires from the AC terminal block and grounding point on the three-phase wye AC power supply (Figure 2), Loosen each screw, and remove each wire from the grounding point or input terminal.

   Note: The terminal connections have either slotted screws or hex screws. Use a 1/4-in. slotted screwdriver for the slotted screws. Use a 5/32-in (4-mm) Allen wrench for the 5/16-in hex screws.

   1. Remove the wire labeled N from the N input terminal
   2. Remove the wire labeled L3 from the L3 input terminal.
   3. Remove the wire labeled L2 from the L2 input terminal.
   4. Remove the wire labeled L1 from the L1 input terminal.
   5. Remove the wire labeled GND from the grounding point labeled GND.

   Figure 2: Disconnecting the AC Power Cord from a Three-Phase Wye AC Power Supply

   
9. Loosen the plastic cable tie fastening the AC power cord to the power supply.
10. Loosen and remove the retaining nut from the AC power cord.
11. Pull the AC power cord out of the metal wiring compartment.
12. Carefully move the AC power cable out of the way.
13. Loosen the captive screws on the lower corners of the power supply faceplate completely.
14. Twist the ejector handles on the upper corners of the faceplate counterclockwise to unseat the power supply.
15. Grasp the handle on the power supply faceplate and pull firmly. Slide it halfway out of the chassis (see Figure 3).

    Caution: Each three-phase wye AC power supply weighs approximately 31.0 lb (14.06 kg). Be prepared to support the full weight of the power supply as you remove it from the router.

16. Place one hand underneath the power supply to support it and slide it completely out of the chassis.

    Figure 3: Removing a Three-Phase Wye AC Power Supply

    

Installing a T640 Three-Phase Wye AC Power Supply

1. Make sure that the voltage across the AC power cord leads is 0 V and that there is no chance that the power cord might become active during installation.
2. Attach an electrostatic discharge (ESD) grounding strap to your bare wrist, and connect the strap to one of the ESD points on the chassis.
3. Switch the power switch on the power supply faceplate to the standby position.
4. Using both hands, slide the power supply into the chassis until you feel resistance (see Figure 5).
5. Twist the ejector handles at the upper corners of the power supply faceplate clockwise until they stop.
6. Tighten the captive screws at the lower corners of the power supply faceplate to secure the power supply in the chassis.
7. Using a slotted screwdriver, loosen the two screws securing the door of the metal wiring compartment.
8. Open the door of the metal wiring compartment.
9. Place the retaining screw into the metal wiring compartment.
10. Unscrew the retaining nut from the AC power cord.
11. Place the retaining nut inside the metal wiring compartment.
12. Put the wires of the AC power cord through the hole of the metal wiring compartment.
13. Screw the retaining nut onto the AC power cord to secure it to the metal wiring compartment.

14. Connect the AC power cord wires to ground and the AC terminal block on the three-phase wye AC power supply (Figure 4). Loosen each of the input terminals or grounding point screws, insert each wire into the grounding point or input terminal, and tighten the screw.

    Note: The terminal connections have either slotted screws or hex screws. Use a 1/4-in. slotted screwdriver for the slotted screws. Use a 5/32-in (4-mm) Allen wrench for the 5/16-in hex screws.

    1. Insert the wire labeled GND into the grounding point labeled GND.
    2. Insert the wire L1 into the L1 input terminal.
    3. Insert the wire labeled L2 into the L2 input terminal.
    4. Insert the wire labeled L3 into the L3 input terminal.
    5. Insert the wire labeled N into the N input terminal

    Figure 4: Connecting Power to the Three–Phase Wye AC Power Supply

    
15. Verify that the power cord wire connections are correct.
16. Using a number 2 Phillips (+) screwdriver, tighten the two captive screws on the metal AC wiring compartment.
17. Place the AC power cord into the plastic tie located on the right side of the power supply, and fasten the plastic tie.
18. Verify that the AC power cord is not touching or blocking access to router components, and that it does not drape where people could trip on it.
19. Remove the ESD grounding strap from the ESD points on the chassis. Connect the strap to an approved site ESD grounding point. See the instructions for your site.
20. Connect the AC power cord to the AC power source.
21. Switch on the customer site circuit breakers to provide voltage to the AC power source cables.
22. Remove the ESD grounding strap from the approved site ESD grounding point. See the instructions for your site. Reconnect the strap to one of the ESD points on the chassis.
23. Verify that the AC OK LED on the power supply faceplate is lit steadily, indicating that the AC terminal block is receiving power.
24. Switch the power switch on the power supply to the ON position (|).
25. Verify that the DC OK LED on the power supply faceplate is lit steadily, indicating that the power supply is correctly installed and is functioning properly. The DC OK LED blinks momentarily, then lights steadily.

    Note: After a power supply is powered on, it can take up to 60 seconds for status indicators—such as the LEDs on the power supply, the command output displays, and messages on the LED display on the craft interface—to indicate that the power supply is functioning normally. Ignore error indicators that appear during the first 60 seconds.

Figure 5: Installing a Three-Phase Wye AC Power Supply