Owner's Manual

Your system supports
Up to four 750 W, 1100 W, and 1600 W (when available) AC power supply modules
Or
Up to four 1100 W DC power supply modules
NOTE: You can install only one 1600 W power supply on each side of the system.
When two identical power supplies are installed, the power supply configuration is redundant (1 + 1). In redundant
mode, power is supplied to the system equally from both power supplies to maximize efficiency.
When only one power supply is installed, the power supply configuration is non-redundant (1 + 0). Power is supplied to
the system only by the single power supply.
NOTE: If two power supplies are used, they must be of the same type and have the same maximum output power.
Hot Spare Feature
Your system supports the Hot Spare feature that significantly reduces the power overhead associated with power
supply redundancy.
When the Hot Spare feature is enabled, a redundant power supply is switched to a sleep state. The active power supply
supports 100% of the load, thus operating at higher efficiency. The redundant power supply in the sleep state monitors
output voltage of the active power supply. If the output voltage of the active power supply drops, the redundant power
supply in the sleep state returns to an active output state.
The active power supply can also activate a sleeping power supply if having both power supplies active is more efficient
than having the redundant power supply in a sleep state. The power supply defaults are to wake both power supplies if
the load on the active power supply is greater than 50% and to sleep the redundant power supply if the load falls below
20%.
You can configure the Hot Spare feature using the iDRAC settings. For more information on iDRAC settings, see the
iDRAC7 User's Guide at dell.com/support/manuals.
Removing An AC Power Supply
CAUTION: Many repairs may only be done by a certified service technician. You should only perform
troubleshooting and simple repairs as authorized in your product documentation, or as directed by the online or
telephone service and support team. Damage due to servicing that is not authorized by Dell is not covered by your
warranty. Read and follow the safety instructions that came with the product.
CAUTION: The system requires one power supply for normal operation. On power-redundant systems, remove and
replace only one power supply at a time in a system that is powered on.
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