Chapter 9: Troubleshooting
112
Problem 8: The Switch ID LED on the front of the switch is flashing the
letter “F.”
Solutions: One or more of the following problems has occurred:
A cooling fan has failed.
The input voltage on the power supply is outside the normal
operating range.
The internal temperature of the switch has exceeded the normal
operating range, and the switch may shut down.
Contact your Allied Telesis sales representative for assistance.
Problem 9: The AT-GS924MPX or AT-GS948MPX Switch is not providing
power to a PoE device.
Solutions: Try the following:
Review the PD’s documentation to confirm that the device
supports Alternative B of the IEEE 802.3at standard. Alternative B
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 Alternative B, the
power is carried on pins 4, 5, 7, and 8 on the RJ-45 port, the same
pins that carry the network traffic. The other mode, Alternative A,
defines pins 1, 2, 3, and 6 as the power carriers. The
AT-GS924MPX and AT-GS948MPX Switches do not support
Alternative A. 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
Alternative A will not work with the switches.
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 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.
To Next Page
Loading...
