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Connecting AC Power to a T640 Router with Three-Phase Delta AC Power Supplies


You connect AC power to the router with three-phase delta AC power supplies by connecting the AC power cord from an AC power supply to an AC power source.

To connect an AC power cord to an AC power source:

  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 off the customer site circuit breakers. Ensure that the voltage across the AC power source is 0 V and that there is no chance that the voltage might become active during installation.
  3. Detach the ESD grounding strap from the approved site ESD grounding point, and connect the strap to one of the ESD points on the chassis.
  4. Switch the power switch on the power supply faceplate to the standby position.
  5. Using a number 2 Phillips (+) screwdriver, unscrew the two captive screws located on the right side of the metal AC wiring compartment.
  6. Open the metal door of the metal AC wiring compartment.
  7. Unscrew the retaining nut from the AC power cord.
  8. Place the retaining nut inside the metal wiring compartment.
  9. Put the wires of the AC power cord through the hole of the metal wiring compartment.
  10. Screw the retaining nut onto the AC power cord to secure it to the metal wiring compartment.
  11. Connect the wires to the AC terminal block on the three-phase delta AC power supply (Figure 1). Loosen the input terminal or grounding point screw, insert each wire into the grounding point or input terminal, and tighten the screw.


    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 labeled 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.
    Figure 1: Connecting Power to a Three-Phase Delta AC Power Supply
Power to a Three-Phase Delta AC Power Supply

    The color of each AC power wire might vary.

  12. Verify that the power cable connections are correct.
  13. Using a number 2 Phillips (+) screwdriver, tighten the two captive screws on the metal AC wiring compartment.
  14. Use the provided plastic cable tie to fasten the AC power cord to the power supply.
  15. 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.
  16. Repeat the procedure for the other three-phase delta AC power supply.