PoE/PoE+ Planning and Implementation Guide 2011-09

2-21
Operating Rules
Provisioning Power for PoE
Table 2-12. Maximum Power Allocations for the E3800 PoE+ Switches
Table 2-13. PoE Power Requirements
The E3800-24G-PoE+-2SFP+, E3800-24G-PoE+-2XG switches and the E3800-
48G-PoE+-4SFP+, E3800-48G-PoE+-4XG switches have 24 or 48 ports
respectively and depending on how many power supplies are installed and to
what voltage the power supply is connected to, either 110 or 220 voltage can
supply up to 1080 watts for PoE/PoE+ usage.
PoE/PoE+ Allocation Using LLDP Information
A PoE port can automatically configure certain PoE+ link partner devices if
the device supports advertising of its PoE needs.
By enabling PoE LLDP detection, available information about the power
requirements of the PD may be used by the switch to configure the power
allocation. The initial configuration for PoE ports may change if more accurate
configuration information is provided by way of LLDP.
Note By default, LLDP on each switch is enabled. PoE+ (802.3at) Powered Devices
(PD) that only support 2-event class signature may not be able to negotiate
for additional power when connected to the switch. In such cases, the LLDP
option on the switch port must be disabled to enable the 2-event classification
so that such PoE+ PDs may be detected. For information on CLI commands
to disable LLDP, see the Management and Configuration Guide for your
switch at www.hp.com/networking/support.
PoE Devices One power supply Two power supplies
PoE for the
E3800-24G-PoE+-2SFP+
and
E3800-24G-PoE+-2XG
switches
573 watts available to ports 1-24 with 127 W
being used by the system at 110 volts.
Or when connected to 220 volts there will be
873 W available for PoE+.
1080 watts available to ports 1-24 with 127 W
being used from the first power supply by the
system at 110 volts.
Or when connected to 220 volts there will be 1080
W available for PoE+.
PoE for the
E3800-48G-PoE+-4SFP+
and
E3800-48G-PoE+-4XG
switches
573 watts available to ports 1-48 with 127 W
being used by the system at 110 volts.
Or 815 watts available to ports 1-48 with
185W being used by the system at 220 volts.
1080 watts available to ports 1-48 with 127 W
being used from the first power supply by the
system at 110 volts.
Or 1080 watts available to ports 1-48 with 185 W
being used by the system at 220 volts.