HP ProCurve 600, Планирование и руководство по внедрению

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2-8
Operating Rules
PoE Power Characteristics
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PD Power Requirements
When a PD is initially connected to a PoE port, a minimum of 17 watts of
available power is required to begin the power-up sequence. This 17 watts is
needed to determine the type of PD requesting power (see “PD Power
Classification” on
page 2-7 ). Once the power classification is determined and
power is supplied, any power beyond the maximum power requirements for
that class of PD is available for use.
In the default switch configuration all PoE ports have a Low priority. If the
switch has less than 17 W of PoE power available, the switch transfers power
from lower-priority ports to higher-priority ports.
See “Switch Priority Class” on page 2-5 for information on the use of PoE port
priority classifications. Within each priority class, a lower numbered port is
supplied power before a higher numbered port.
Disconnecting a PD from a port causes the switch to stop providing power to
that port and makes that power available to other ports configured for PoE
operation.