3Com IntelliJack NJ2000 Quick Start Manual page 7

1. Understand the Power Options
Power to the NJ2000 can be supplied in one of these ways:
Through PoE (either 802.3at or 802.3af) applied to the uplink port
•
or
Through the optional local external power supply
•
If power is supplied to the uplink port by 802.3at or by the external power
supply, then ports 1 and 2 may act as PoE PSE (Power Source Equipment) and
may also provide power to other devices plugged into those ports.
If power is supplied by 802.3af, then port 1 and 2 will not be able to supply
PoE power.
2. Understand the PoE Capabilities for Port 1 and Port 2
If power is supplied by 802.3at through the uplink port (PD) or if power is
supplied through the external power supply, then ports 1 and 2 may in turn
act as PoE PSE and may provide power.
If power is provided to the NJ2000 by the uplink port (PD) with 802.3at PoE or
with the external power supply, then the NJ2000 will have a total PoE PSE
budget of 15.4W, which can be divided between port 1 and port 2 based on
the class-based power management feature.
The NJ2000 can power these combinations of devices:
One Class 0,3 PD device or
•
Two Class 2 PD devices or
•
Two Class 1 PD devices or
•
One Class 1 PD device and One Class 2 PD device
•
CAUTION: You must use only a power supply that is provided or approved by
3Com for use with this NJ2000. Failure to comply with this requirement may
result in damage to the NJ2000, or may result in a hazardous situation or
personal injury.
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