EMC AX100/150's Power Supply's behavior

An India customer, report a fault for his EMC's AX100 with dual Storage Processor. He sent me the SPCollect, found that there is error for SPB, and Power Supply B. Due to this storage contained all critical information for his company, I have to arrange the onsite service with 2 standby parts: Storage Processor, and Power Supply.

Few hours later, onsite engineer feedback, and the call routed to me. After few checking with engineer, we confirmed that issue caused by human error, and there isn't any hardware fault from the AX100 when engineer reach site.

Cause:
Customer did accidentally disconnect the power cord to Power Supply B, and cause SPB down.

The behavior of the power supply as below:

1. A failed power supply prevents operation of a single-processor AX-series
2. On a dual-processor AX100, a failed power supply will power down the associated storage processor
3. On a dual-processor AX150 or an AX150SC with two power supplies, a failed power supply will cause the system to run in degraded mode.