Connecting a 750 W DC Power Supply to the Source Voltage

About this task

Two 750 W DC power supplies are available: model XN-DCPWR-750W-F (front-to-back airflow) and model XN-DCPWR-750W-R (back-to-front airflow). Both can connect to a –48 V power source.

The DC power connection at your facility must be made by a qualified electrician, following these instructions.

Warning

Warning

Always make sure that the DC circuit is de-energized before connecting or disconnecting the DC power cables on the DC power supply.
Caution

Caution

Provide proper connection and strain relief on the DC power cables in accordance with all local and national electrical codes.

Procedure

  1. Verify that the DC circuit is de-energized.
  2. Attach an ESD-preventive wrist strap to your bare wrist and connect the metal end to an appropriate ground point on the rack.
  3. Connect the negative wire (–48 V) to the power supply as follows:
    1. Insert the stripped end of the wire all the way into the leftmost of the three slots on the terminal block.
      Refer to Slots for Connecting Wires to the 750 W DC Power Supply for slot locations.
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      Slots for Connecting Wires to the 750 W DC Power Supply
      Diagram of terminal block showing (in order) negative, ground, and positive connectors
    2. Insert a #1 Phillips screwdriver into the hole below the slot, and tighten.
    3. Gently tug the wire to make sure it is fastened securely.
  4. Connect the positive wire (–48 V) as follows:
    1. Insert the stripped end of the wire all the way into the rightmost of the three slots on the terminal block.
    2. Insert a #1 Phillips screwdriver into the hole below the slot, and tighten.
    3. Gently tug the wire to make sure it is fastened securely.
  5. Connect the cables to the DC source voltage, using hardware appropriate to the installation site and following local and national electrical codes.

What to do next

Turn on the switch, following the steps in Connecting Power to the Switch.

Leave the ESD strap permanently connected to the rack, so that the strap is always available when you need to handle ESD-sensitive components.