Hot Spare Feature; Removing A Redundant Power Supply - Dell PowerEdge R430 Owner's Manual

• 550 W AC (redundant)
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.
NOTE: For AC power supplies, use only PSUs with the Extended Power Performance (EPP) label on
the back. Mixing PSUs from previous generations of Dell PowerEdge servers can result in a PSU
mismatch condition or failure to power on.

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, one of the redundant PSUs is switched to the sleep state. The
active PSU supports 100 percent of the load, thus operating at higher efficiency. The PSU in the sleep
state monitors output voltage of the active PSU. If the output voltage of the active PSU drops, the PSU in
the sleep state returns to an active output state.
If having both PSUs active is more efficient than having one PSU in the sleep state, the active PSU can
also activate the sleeping PSU.
The default PSU settings are as follows:
• If the load on the active PSU is more than 50 percent, then the redundant PSU is switched to the
active state.
• If the load on the active PSU falls below 20 percent, then the redundant PSU is switched to the sleep
state.
You can configure the hot spare feature by using the iDRAC settings. For more information about iDRAC
settings, see the Integrated Dell Remote Access Controller User's Guide available at Dell.com/
idracmanuals.

Removing a redundant power supply

Prerequisites
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.
1. Ensure that you read the
2. Disconnect the power cable from the power source.
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Safety instructions.