DS8000 Service Documentation Version 7.5

MAP2330 Repair rack ground continuity

About this task

The previous procedure measured more than 0.1 ohm resistance between the ground pin or ground wire of the mainline power cable and the primary power supply enclosure. Follow these steps to check and repair the ground continuity problem.
  1. If you are repairing a Model 941, 94E, 951, or 95E, go to MAP2330 Section-1.
  2. If you are repairing a Model 961 or 96E, go to MAP2330 Section-2.
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MAP2330 Section-1

Procedure

  1. Disconnect the failing mainline power cable Callout label 1 or Callout label 2 from the failing PPS.
    Figure 1. Mainline power cables (Model 94x)
    Base rack mainline power cables (Model 94x)
  2. Prepare the multimeter to measure 0.1 ohm or less resistance.
  3. For connector information, refer to Figure 2 or Figure 3 .
    Figure 2. Three-phase amp
    Three-phase amp
    Figure 3. Single phase, ground pin
    X3550 management console server LEDs (rear view)
    • For the mainline power cable (plug in): Place one lead of the multimeter on the ground pin of the male plug on the mainline power cable.
    • For the mainline power cable (wired): Place one lead of the multimeter on the green and yellow wire at the customer end of the mainline power cable.
  4. Place the other lead on the ground pin of the female connector on the mainline power cable. See Figure 4 or Figure 5.
    Figure 4. Three-phase delta mainline power connector at DC-UPS end
    Three-phase mainline power connector
    Figure 5. Single phase mainline power connector
    Single phase, mainline power connector

    Is there 0.1 ohm or less resistance?

    • Yes, the mainline power cable is good but the primary power supply enclosure is not grounded. Go to step 6.
    • No, the mainline power cable ground lead is open or has resistance, continue with the next step.
  5. Perform the following steps if, the ground lead on the Mainline Power Cable is open or has resistance.
    1. Replace the mainline power cable.
    2. Return to Preparing to check the storage facility and customer power. Verify that the ground continuity now measures 0.1 ohm or less resistance.
  6. The primary power supply enclosure is not grounded. Replace the primary power supply.
    1. Go to Exchange the PPS (primary power supply) in the Exchanging parts section of this Information Center.
    2. Return to Preparing to check the storage facility and customer power. Verify that the ground continuity now measures 0.1 ohm or less resistance.

MAP2330 Section-2

Procedure

  1. Disconnect the failing mainline power cable Callout label 1 or Callout label 2 from the failing DC-UPS. See Figure 6.
    Figure 6. Mainline power cables (Model 96x)
    Mainline power cables (Model 96x)
  2. Prepare the multimeter to measure 0.1 ohm or less resistance.
  3. For connector information, refer to Figure 7 or Figure 8.
    • For the mainline power cable (plug in): Place one lead of the multimeter on the ground pin of the male connector at the customer end of the mainline power cable.
    • For the mainline power cable (wired): Place one lead of the multimeter on the green and yellow wire at the customer end of the mainline power cable.
    Figure 7. Three-phase low voltage (200 - 240 V) 60A, IEC60309 cable connector pins
    Three-phase low voltage, 200 - 240 V 60A, IEC60309 cable connector pins
    Figure 8. Single-phase, 200 - 240 V, 60A, IEC60309 cable connector pins
    Single-phase, 200 - 240 V, 60A, IEC60309 cable connector pins
  4. Place the other lead on the ground pin of the mainline power cable connector at the DC-UPS end. See Figure 9, Figure 10, or Figure 11.
    Figure 9. Three-phase delta mainline power connector at DC-UPS end
    Three-phase mainline power connector
    Figure 10. Three-phase high voltage (380 - 415 V) mainline power connector at DC-UPS end
    Three-phase wye mainline power connector
    Figure 11. Single-phase mainline power connector at DC-UPS end
    Single-phase mainline power connector at DC-UPS end

    Is there 0.1 ohm or less resistance?

    • Yes, the mainline power cable is good but the DC-UPS enclosure is not grounded. Go to step 6.
    • No, the mainline power cable ground lead is open or has resistance; continue with the next step.
  5. Perform the following steps if the ground lead on the mainline power cable is open or has resistance.
    1. Replace the mainline power cable.
    2. Return to Preparing to check the storage facility and customer power. Verify that the ground continuity now measures 0.1 ohm or less resistance.
  6. The primary power supply enclosure is not grounded. Replace the primary power supply.
    1. Go to Exchange the DC-UPS DC supply unit (DSU).
    2. Return to Preparing to check the storage facility and customer power. Verify that the ground continuity now measures 0.1 ohm or less resistance.