DS8000 Service Documentation Version 7.5

MAP2041 Check DC-UPS DC supply unit (DSU) input circuit breaker

The DC-UPS DC supply unit (DSU) input circuit breaker is being reported as not in the on position.

Related tasks:
How to start the service information center

MAP2041 Section-1

Procedure

  1. At the rear of the rack, inspect the input circuit breaker (CB1 Figure 2) on the DSU listed in the FRU list.
    Note: DSU location code E1 is the upper DSU, E2 is the lower DSU. See Figure 1.
    Find the condition that applies. The circuit breaker switch is:
    • In the middle position, neither completely up nor completely down. Go to step 2.
    • In the completely up position. Go to step 3.
    • In the completely down position. Go to step 4.
    Figure 1. Base rack locations, front and rear
    Base rack locations, front and rear
    Start of change
    Figure 2. Location codes for the DC-UPS (Models 961, 96E) (rear)
    Location codes for the DC-UPS (Models 961, 96E) (rear)
    End of change
  2. The input circuit breaker is in the center position because it is tripped as a result of an over-current condition inside the DSU. Do not reset the circuit breaker. Return to the screen that sent you here to continue the repair process and replace the DSU FRU.
  3. The input circuit breaker is in the completely up position, which is the normal position. The DSU has previously reported that the breaker was manually tripped and then manually closed. Either someone manually tripped/closed the breaker or the DSU is incorrectly reporting that it detected a manual trip/close. Attempt to determine from the customer whether there has been any manual intervention on the machine. If this is the first occurrence, close the serviceable event and exit this MAP. If this is the second (or more) occurrence of such event and there was no known source of manual intervention (including the customer), then return to the screen that sent you here to continue the repair process and replace the DSU FRU.
  4. The input circuit breaker is in the completely down position, which is the normal position when it has been manually switched off. Determine who switched it off and why.
    • If it was switched off as part of a repair procedure, return to that procedure and continue.
    • If you cannot determine why it was switched off, go to the next step.
  5. Observe the two character LED status display to the right of the input circuit breaker.

    Is an error code displayed?

    • No, go to the next step.
    • Yes, display and repair any related serviceable events.
      • If there is none, go to MAP2341 Codes on the DC-UPS DSU status display.
      • If the error indicates that the circuit breaker is off (display = I4), then go to the next step.
      • If the error is internal to the DSU, replace the DSU.
      • If the error is not internal, contact your next level of support.
  6. The functional code may have fenced the DSU (removed it from active use) as part of the error recovery. Determine if the DSU has been fenced.
    1. From the navigation area, click Storage Facility Management > storage facility.
    2. From the bottom Task area, click Service Utilities > View Storage Facility State.
    3. A window displays the status (passed/failed) of 25 or more system checks.
    4. At the bottom of the System Check Type column, observe the status of the Fenced Resources.

    What is the status of the Fenced Resources?

    • PASSED, no resources are fenced. If the error code from step 5 above indicated that the breaker was off (I4), then flip the breaker to the up (On) position. Go to step 8.
    • FAILED, go to the next step.
  7. Display details about the Fenced Resources.
    1. Select Fenced Resources in the list.
    2. Click Details. The Details window is displayed.

    Is the DSU listed as a fenced resource in the Details window?

    • Yes, go to the next step.
    • No, the DSU is not fenced. Close the serviceable event and exit this MAP. There should be serviceable events for resources that are fenced. These should be repaired.
  8. Reset the DSU fence or related power errors by doing a pseudo repair of the DSU FRU.
    1. Return to the repair screen that sent you here.
    2. Do a pseudo repair of the FRU. A pseudo repair of the DSU means that you use the normal FRU replacement procedure. Disconnect and reconnect the cables in order, when directed. The ground cable can be left connected. Do not physically remove and reinstall the FRU.