HP Compaq Presario,Presario 1910, Руководство пользователя

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Item Description
Power Priority
Set the power supply priority for a PoE port. The priority levels of a PoE port include
low, high, and critical in ascending order.
•
When the PoE power is insufficient, power is first supplied to PoE ports with a
higher priority level.
•
When the PSE power is overloaded, the PoE port with a lower priority is first
disconnected to guarantee the power supply to the PD with a higher priority.
•
If you set the priority of a PoE port to critical , the system compares the
guaranteed remaining PSE power (the maximum PSE power minus the
maximum power allocated to the existing critical PoE port, regardless of
whether PoE is enabled for the PoE port) with the maximum power of this PoE
port. If the former is greater than the latter, you can succeed in setting the
priority to
critical , and this PoE port will preempt the power of other PoE ports
with a lower priority level; otherwise, you will fail to set the PoE port to critical .
In the former case, the PoE ports whose power is preempted will be powered off,
but their configurations will remain unchanged. When you change the priority
of a PoE port from critical to a lower level, the PDs connecting to other PoE ports
will have an opportunity of being powered.
By default, the power priority of a PoE port is low .
IMPORTANT:
•
19 watts guard band is reserved for each PoE port on the device to prevent a PD
from being powered off because of a sudden increase of the PD power. When
the remaining power of the PSE is lower than 19 watts, the port with a higher
priority can preempt the power of the port with a lower priority to ensure the
normal working of the higher priority port.
•
If the sudden increase of the PD power results in PSE power overload, power
supply to the PD on the PoE interface with a lower priority will be stopped to
ensure the power supply to the PD with a higher priority.
Configuring non-standard PD detection
There are standard PDs and nonstandard PDs. Standard PDs are those conforming to the IEEE 802.3af
standard. Usually, the PSE can detect only standard PDs and supply power to them. The PSE can detect
nonstandard PDs and supply power to them only after the PSE is enabled to detect nonstandard PDs.
1. Select PoE > PoE from the navigation tree.
2. Click the PSE Setup tab.
The page displays the location of the PSE, and the status of the non-standard PD detection function.
Figure 511 PSE Setup tab
Enabling the non-standard PD detection function
Perform one of the following tasks on the PSE Setup tab to enable the non-standard PD detection function: