Allied Telesis AT-SBX31GT24 User Manual

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SwitchBlade x3112 Installation Guide
205
Power Over Ethernet
This section applies only to the AT-SBx31GP24 Line Card. Each port on 
the line card has two LEDs. The left LED provides port link and activity 
status and the right LED provides PoE status information. The PoE LED is 
solid green when a port is delivering power to a powered device (PD). The 
PoE LED of a port that is not delivering power will be flashing amber, 
steady amber, or off. If a powered device is not receiving power from a 
port on the line card, try the following:
If all the L/A LEDs on the line cards in the chassis are off, try 
pressing the eco-friendly button on the active master control card 
to turn on the LEDs.
Check to be sure that the chassis has at least one AT-
SBxPWRPOE1 Power Supply and that the unit is operating 
properly. The AC and DC LEDs should be solid green and the 
Fault LED should be off. For troubleshooting suggestions, refer to 
“AT-SBxPWRSYS1 and AT-SBxPWRPOE1 AC Power Supplies” 
on page 198.
Review the PD’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 on 
the line card to the PD. 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 AT-SBx31GP24 Line Card does 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 this line card.
Check that the device’s power requirements do not exceed 30 W. 
This can be verified by reviewing the device’s documentation or 
data sheet.
Verify that you are using the appropriate category of twisted-pair 
cable by referring to Table 2 on page 37.
Use the SHOW POE INTERFACE command in the management 
software to determine whether PoE is enabled on the port. The 
default setting for PoE is enabled.
Use the SHOW POE INTERFACE command to determine whether 
the PoE power setting for the port has been reduced to a value 
below the power requirements of the device.