Allied Telesis AT-GS950/10PS - Manual (Page 22)

Chapter 1: Overview
22
Power over Ethernet (PoE)
Power over Ethernet technology permits both power and data to be
transmitted over an Ethernet cable. Both PoE (IEEE802.3af) and PoE+
(IEEE802.3at) are supported on the 10/100/1000T ports on the
AT-GS950/10PS, AT-GS950/16PS, and AT-GS950/48PS switches. Here
is a summary of the PoE feature:

Powered device classes 0,1, 2, 3 and 4 are supported.

Port prioritization is provided on all PoE ports.

The default configuration is DISABLED on all PoE switch ports.

The PoE configuration parameters can be set through the switch’s
web management interface.
The maximum number of ports that the AT-GS950xx/PS switches will
support when only one class of service is required from the powered
devices connected to the PoE ports is shown in Table 1.
Note
Each switch can support any combination of PoE classes 0 - 4
simultaneously up to the maximum PoE power that is available from
the switch.
Port Power Priority
When the power budget for the switch is reached, each port is allotted
power according to its priority level. You can set the power priority of each
PoE port to one of three levels: Low, High, and Critical. The default is Low.
If the priority level of all the ports is set to the same value, the lowest port
number has the highest port power priority. For instance, if you connect
eight class 4 powered devices to ports 1 - 8 on an AT-GS950/16PS
switch, the PoE power budget is exceeded, and some ports will have the
PoE power turned off. The ports allowed to transmit power are determined
by the Port Priority feature. In this case, port 1 has the highest power
priority level and transmits PoE power followed by port 2, etc., through port
6 while ports 7 and 8 are not allowed to transmit any PoE power.
Table 1. Max Ports Supported per PoE Class
Switch PoE Ports
Max PoE
Power
Available
Class 2
IEEE 802.3af
(7W per Port)
Class 3
IEEE 802.3af
(15.4W per Port)
Class 4
IEEE 802.3at
(30W per Port)
AT-GS950/10PS Ports 1 - 8 75 W 8 Ports 4 Ports 2 Ports
AT-GS950/16PS Ports 1 - 16 150W 16 Ports 12 Ports 6 ports
AT-GS950/48PS Ports 1 - 24 370W 24 Ports 24 Ports 12 ports