PoE/PoE+ Planning and Implementation Guide 2011-09

2-19
Operating Rules
Provisioning Power for PoE
PoE Power Requirements
The Switch 3500yl-24G-PWR has 24 ports with an internal PoE power supply
that provides 398 watts of 50V power across all 24 ports. The Switch 3500yl-
48G-PWR has 48 ports with 398 watts of 50V power across all 48 ports. There
is a special power provision on the Switch 3500yl-48G-PWR, Where the switch
reserves 22 watts for each bank of 24 ports, ports 1-24 and 25-48, so that neither
set of ports receives the entire 398 watts. This is designed for the integrity and
safety of PoE during power balancing to properly detect PDs and bring them
online.
PoE/PoE+ Allocation Using LLDP Information
You can have the port automatically configure certain PoE link partner devices
if the devices supports advertising of its PoE needs. By enabling PoE LLDP
detection, available information about the power usage of the PD will be used
by the switch to configure the power allocation. The default configuration is
for PoE information to be ignored if detected through LLDP.
For more information, see the Management and Configuration Guide for
your switch at www.hp.com/networking/support.
HP ProCurve 3500yl PoE+ Switches
Maximum PoE Power
The Switch 3500yl-24G-PoE+ provisions (allocates power to) ports 1-24 with
398 watts of power for PoE and PoE+ applications compatible with the IEEE
802.3af and the 802.3at standard and some pre-standard devices. The Switch
3500yl-48G-PoE+ provisions ports 1-48 with 398 watts. This reduces the
average per port wattage by half as compared to the Switch 3500yl-24G-PoE+.
An external power supply, the HP 630 Redundant and/or External (HP 630
RPS/EPS) power supply (J9443A) can be connected to either of the 3500yl
PoE+ switches to provide redundant or extra PoE+ power. The HP 630 RPS/
EPS provides up to 388 watts of PoE+ power at 54 volts. The 630 RPS/EPS
power supply is rated at 398 watts, however, 388 watts are supplied to the
switch due to line loss on the EPS cable.