Allied Telesis GS950 PS Series, Руководство по установке, Страница: 94 / 108

Chapter 8: Troubleshooting
94
Power Over Ethernet
A switch port is not supplying power to a PoE device. Try the following:
 Use the management software to determine whether the switch
has already reached its maximum power budget of 185W and
cannot support additional powered devices.

Review the powered device’s documentation to confirm that it
supports Mode A of the IEEE 802.3at standard. Mode A is one of
two modes that define the connector pins that deliver the power
from the port in the switch to the powered device. In Mode A, the
power is carried on pins 1, 2, 3, and 6 on the RJ-45 port, the same
pins that carry the network traffic. The second mode, Mode B,
defines pins 4, 5, 7, and 8 as the power carriers. The GS950 PS
V2 Switches do not support Mode B. Most powered devices are
designed to accept power by either mode, but some legacy
devices may only support one mode. This can be verified by
reviewing the device’s documentation or data sheet. Legacy
devices that only support Mode B will not work with the switches.
 Verify that the device’s power requirements do not exceed 25.5 W.
This can be confirmed by reviewing the device’s documentation or
data sheet.
 Verify that you are using the appropriate category of twisted-pair
cable. Refer to Table 1 on page 24.

Use the management software on the switch to determine whether
PoE is enabled on the port. The default setting for PoE is enabled.
 Use the management software on the switch to determine whether
the PoE power setting for the port has been reduced to a value
below the power requirements of the device.
 Try connecting the device to a different port on the switch.