Dell Precision 7920 Rack, Руководство пользователя

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Form
Factor
Type Spee
d
Rotational
Speed
Capacities
3.5" SATA 6Gb 7.2K 1TB, 2TB, 8TB
Table 25. Supported Drives - NVMe PCIe SD
Description
256GB Device
512GB Device
1TB Device
Power supply units
The power supply unit (PSU) is an internal hardware component which supplies power to the components in the system.
Your system supports the following:
• Two 1600 W or 1100 W AC power supply units (PSUs)
NOTE: For more information, see the Technical specifications
section.
CAUTION: If two PSUs are installed, both the PSUs must have the Extended Power Performance (EPP) label. Mixing PSUs
(even the PSUs that have the same power rating) from previous generations of Precision workstation is not supported. This
results in a PSU mismatch condition or failure to turn the system on.
NOTE: Titanium PSU is nominally rated for 200 V AC to 240 V AC input only.
NOTE: When two identical PSUs are installed, power supply redundancy (1+1 – with redundancy or 2+0 – without redundancy) is
configured in system BIOS. In redundant mode, power is supplied to the system equally from both PSUs when Hot Spare is
disabled. When Hot Spare is enabled, one of the PSUs will be put into sleep mode when system utilization is low in order to
maximize efficiency.
NOTE: If two PSUs are used, they must be of 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 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
Dell.com/idracmanuals .
Technology and components 95