Table 3. Psu System Configurations - Dell External OEMR R910 Technical Manual

Dell
The power supply bay is designed to prevent unsupported power supplies from being installed. Mixing
of 1100W and 750W power supplies is not supported. R910 power supplies have embedded cooling
fans and one bi-colored status LED.
The PowerEdge R910 PSUs have a FRU EEPROM; FRU data is stored in the memory of the PSU
Microcontroller. PSU Firmware can be updated by iDRAC over the PMBus. Power is "soft-switched,"
allowing power cycling via a switch on the front of the system enclosure or through a software control
(through server management functions). The power system is compatible with industry standards, such
as ACPI and the Microsoft Windows Server Hardware Design Guide.
If not using all 4 power supplies, it is preferred that the power supply be installed starting from PS1 bay
in order to avoid power loss in the PDB Copper planes. However, there is nothing that prevents the use
of the rest of the bays in that case. The empty bays should be populated with the PS sheet metal
blanks for thermal reasons.
The power supplies connect indirectly to the planar via the Power Distribution Board (PDB). There is
a power cable that connects between the PDB and the backplane. Another cable also connects the
PDB to the optical and/or tape drives.
R910 has 4 power supply bays. PSU system configurations are shown in Table 3.
High Output Power Supply (1100W), Non-Redundant configuration (1+0)
High Output Power Supply (1100W), Redundant Energy Optimal configuration (1+1)
High Output Power Supply (1100W), Non-Redundant Full-power configuration (2+0)
High Output Power Supply (1100W), Fail-over configuration (2+1)
High Output Power Supply (1100W), Redundant Full-power configuration (2+2)
Energy Smart Power Supply (750W), Non-Redundant configuration (1+0)
Energy Smart Power Supply (750W), Redundant Energy Optimal configuration (1+1)
Energy Smart Power Supply (750W), Non-Redundant Full-power configuration (2+0)
Energy Smart Power Supply (750W), Fail-over configuration (2+1)
Energy Smart Power Supply (750W), Redundant Full-power configuration (2+2)
There are two different redundancy modes with 2 PSUs present in the system. One is (2+0) non-
redundant capable of running full system configuration, and the other is (1+1) redundant running
limited configuration. The user could switch the mode between (1+1) and (2+0) via iDRAC GUI only
for the two PS case depending on if the system is capable of supporting the new mode or not. The
other modes of redundancy are automatics based on the functional supplies present at the time
when AC is applied and system is powered ON. See
for more information.
In the (2+2) mode, if the power supplies are evenly split across two separate grids on the AC line
side, then this mode would also be considered ―AC or Grid‖ redundant in addition to power.
The system power distribution consists of one, two, three or four AC-to-DC power supplies connected
to the planar through the PDB. The power supply only provides +12V and +12Vaux. The power
supplies connect directly to the planar via the Power Distribution Board (PDB). There are no cables
involved for delivering the power from the PSUs to the motherboard.
The 12V power is then distributed to the rest of the subsystems like the backplane and optical drive
from the motherboard using cables. There are several voltage regulators in the system to supply
different voltage levels needed by different logic devices.
Dell PowerEdge R910 Technical Guide
PSU System Configurations
Table 3.
Power Supplies in the Hardware Owner's Manual
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