NEC SMB8000, Руководство пользователя

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5 - 8 Gigabit PoE Switch Web Manager
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Issue 3.0 SMB8000
Once a PD connects to a port and begins operating, the system power budget
availability is reduced by the maximum limit of the PD’s power classification. Thus, if
there is less than 15.4 watts available, the priority methods described above are used.
For example, with 20 watts of PoE power remaining available on the switch, you can
connect any class (0~3) new PD without losing power to any currently connected
PDs.
Now, assume there are PDs connected and powered on ports 1, 2, and 5. And let’s
say all PoE power priorities are set to Low, and there is only 14.6W remaining. If the
next PD you connect is a class 3 device (15.4 watts max power delivery), and is
connected to port 3, then power will be removed from the higher-numbered port
number 5 and be given to the new PD in the lower-numbered port 3.
However, if the PoE power priority is set to High or Critical on port 5, then a new PD
plugged to port 3 would not be allowed to power up, since lower numbered ports 1
and 2 have higher priority than port number 3.
The Power over Ethernet Configuration screen allows users to manage and configure
Power over Ethernet settings. The following assignments can be made for each port:
z
Admin State – Indicates whether PoE is enabled or disabled on the port.
z
Priority – Priority Indicates the PoE Priority setting of the port. The possible
values are Critical, High, Low (default).
z
ETIA Cards in Chassis – Refer to Table 5-1 Maximum Power – Blades to
determine the maximum power per blade.
Table 5-1 Maximum Power – Blades
Blade(s)
Maximum Power
(Each Blade)
1 90W
2 45W
3 30W