Figure 19. M1000E Power Supply - Dell PowerEdge M1000e Technical Manual

Figure 19. M1000e power supply

Dell power supplies use output ORing FETs to isolate the power supply from the 12V system bus. If a
single power supply fails its output ORing FET, the power supply will turn off removing itself from
the bus like an electrical switch that turns off when the power supply fails.
When DPSE is enabled, the PSU units move between on and off states depending on actual power
draw conditions to achieve high power efficiency.
In the N+N power supply configuration, a system provides protection against AC grid loss or power
supply failures. If one power grid fails, three power supplies lose their AC source, and the three
power supplies on the other grid remain powered, providing sufficient power for the system to
continue running. In the N+1 configuration, only power supply failures are protected, not grid
failures. The likelihood of multiple power supplies failing at the same time is remote. In the N+0
configuration, there is no power protection and any protection must be provided at the node or
chassis level. Typically this case is an HPCC or other clustered environment where redundant power
is not a concern, since the parallelism of the processing nodes across multiple system chassis
provides all the redundancy that is necessary.
The midplane carries all 12V DC power for the system, both main power and standby power. The
CMCs, LCD and control panel are powered solely by 12V standby power, ensuring that chassis level
management is operational in the chassis standby state, whenever AC power is present. The server
modules, I/O modules, fans and iKVM are powered solely by 12V main power.
PowerEdge M1000e Technical Guide
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