Exchange the power distribution unit (PDU)

Before you begin

Icon for electrostatic discharge wrist strapUse approved ESD procedures to prevent damage.

Attention:
  • This procedure is not a stand-alone procedure. Customer disruption and damage to the hardware might occur when microcode and power boundaries are not in the proper conditions for this service action.
  • If a serviceable event FRU repair directed you to this procedure, the microcode and power boundaries are already set.
  • If a serviceable event FRU repair did not direct you to this procedure, see MAP1230 Replace a FRU without using a serviceable event.
Notes:
  • All the cables and FRUs to be removed must be uniquely identified so they can be reinstalled correctly.
  • If an installed earthquake resistance kit prevents you from accessing this FRU, refer to MAP1600.
DANGER
Hazardous voltage, current, or energy levels are present inside of a component to which this label is attached. (L001)
Safety label L001

Remove the power distribution unit (PDU)

Procedure

  1. Open the left rear cover. Remove the two screws Callout label 1 that secure the right rear cover (trained service personnel access area only).
    Open the right rear cover. (Figure 1)
    Note: The screws must be reinstalled when the cover is closed to prevent customer access.
    Figure 1. Removing retaining screws on right rear machine cover
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  2. To locate this FRU, do one of the following and then return here and continue to replace the FRU:
    • If this FRU has a FRU identify indicator, use the FRU identify indicator, which is listed in MAP1240 Locating FRUs by using identify indicators. If not, use the location code.
      Note: There may be cases where the FRU failure or fencing conditions prevent the FRU LED indicator from being lit even if the FRU has power.
    • Use the location code, which is listed in MAP1245 Finding FRUs by using location codes. (Figure 2)
    • If there is no FRU identify indicator or location code, you were sent here by an isolation MAP or symbolic FRU procedure. Use the information in that procedure as well as the figures in this procedure to locate the proper part to exchange.
    Figure 2. Locations for power distribution units
    Locations for power distribution units
  3. Most, but not all, FRUs have identify indicators. Use the blinking amber or solid blue FRU identify indicators to ensure that you are working on the correct enclosure and/or FRU.
  4. Unfasten Callout label 1 and then rotate all six power distribution units (PDUs) away from the rear of the rack.
    Note: The PDU service tools should not be used to hold the PDUs open in the service position. The forces of moving the PDU being replaced out of alignment with the adjacent PDUs could bend the tools.
    Figure 3. Power distribution units in normal position (rack rear view)
    Power distribution units in normal position (rack rear view)
  5. Remove the PDU alignment bracket.
    1. The upper three PDUs are held in a group by a PDU alignment bracket. The lower three PDUs are held in a group by a PDU alignment bracket.
    2. Pull the spring plunger Callout label 3, slide the alignment bracket Callout label 2 up and remove it.
    Figure 4. PDU alignment bracket
    PDU alignment bracket
  6. Disconnect the PDU power input cables J9 Callout label 1 and J10 Callout label 2 from the right side.
    Figure 5. Locations for power distribution unit (PDU) connectors
    Locations for power distribution unit (PDU) connectors
  7. Unlatch and disconnect all power output cables J1-J8 Callout label 3 (Figure 5).
  8. Unlatch and remove any dummy plugs from the left side of the PDU. Move them to the new PDU and install them on the same connectors.
  9. If the new PDU has a yellow and green ground cable pre-attached, disconnect the existing yellow and green ground cable from the rack.
    Retain the nut and star washer for use with the new PDU.
  10. If the new PDU does not have a yellow and green ground cable pre-attached, disconnect the existing ground cable from the old PDU.
    Retain the nut and star washer for use with the new PDU.
  11. Remove the PDU to be replaced by rotating it away from the partner PDUs to allow it to be lifted up and off the hinge pins.

Install the power distribution unit (PDU)

Procedure

  1. Install the new PDU by aligning the hinge pins and lowering the unit into place.
  2. Connect the yellow and green ground cable.
    1. Place the star washer onto the threaded stud.
    2. Place the PDU ground cable lug on the threaded stub.
    3. Secure the ground lug with the lock nut.
  3. Connect the J9 Callout label 1 (upper) and J10 Callout label 2 (lower) power input cables. (Figure 5)
    Note: Cross connecting these two cables can cause problems and can cause manual power isolation procedures to fail.
  4. Connect and latch the PDU output power cables (J1-J8) Callout label 3 (Figure 5).
  5. Install the PDU alignment bracket and ensure the spring plunger secures it in place.
  6. Rotate and fasten the PDUs to the closed position.
  7. Close the right rear cover and reinstall the two security screws that prevent customer access. Then close the left rear cover.
  8. Exit this service information center parts exchange procedure and return to the procedure that sent you here.