Allied Telesis AT-8516F/SC Installation Manual page 75

Verify that the twisted pair cable is Category 5 or 5E.
Verify that the twisted pair cable is not faulty.
Use the AT-S62 management software to determine whether PoE
is enabled on the switch and the port. The default setting for PoE
is enabled.
Use the management software to determine whether the PoE
power setting for the port has been reduced from the default
setting of 15.4 W, to a value below the power requirements of the
device.
PoE is not supported on expansion modules.
Verify that the power budget on the switch is not being exceeded
by the powered devices. This should not be a problem for the
AT-8524POE switch, which can support powered devices on all
ports 1 to 24, even when all devices require the maximum of 15.4
W.
Check the FAULT LED. During normal operations, the LED remains off,
except for periods when the management software is saving a change to
its configuration. If it remains on for an extended period, do the
following:
Try resetting the switch by disconnecting and reconnecting the
AC power cord. If the switch is a DC model, reset the unit by
powering off and the powering on the DC circuit.
If the FAULT LED remains ON, try downloading a new version of
the switch's management software through the RS-232 terminal
port on the front panel of the switch. For instructions, refer to the
switch's software management guide.
If the LED remains on even after you have tried the above
suggestions, the switch may be having a hardware problem.
Contact your Allied Telesyn representative for assistance.
If you are unable to establish a local management session with the
switch through the RS-232 terminal port on the front panel, do the
following:
Check to be sure that the RS-232 cable is securely connected to
the RS-232 terminal port on the switch and to the RS-232 port on
the terminal or personal computer.
Check to be sure that you are using a straight-through RS-232
cable. Do not use a cross-over cable.
AT-8500 Series Fast Ethernet Switch Installation Guide
75