Hot spare feature
Your system supports the hot spare feature that significantly reduces the power overhead associated with power supply unit
(PSU) 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 system 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 of PSU rated power wattage, then the redundant PSU is switched to
the active state.
●
If the load on the active PSU falls below 20 percent of PSU rated power wattage, 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, see the
iDRAC User’s Guide
available at
https://www.dell.com/poweredgemanuals
Removing a power supply unit blank
Prerequisites
Follow the safety guidelines listed in the
.
Steps
Pull the blank out of the system.
CAUTION:
To ensure proper system cooling, the PSU blank must be installed in the second PSU bay in a
non-redundant configuration. Remove the PSU blank only if you are installing a second PSU.
Figure 126. Removing a power supply unit blank
Next steps
1. Replace the power supply blank or
.
Removing a power supply unit
Prerequisites
CAUTION:
The system requires one power supply unit (PSU) for normal operation. On power-redundant
systems, remove and replace only one PSU at a time in a system that is powered on.
1. Follow the safety guidelines listed in the
.
2. Disconnect the power cable from the power outlet and from the PSU you intend to remove.
3. Remove the cable from the strap on the PSU handle.
Installing and removing system components
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