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If you find any problems, please take the following steps to check.
◆ LED
The POWER LED (Power) is not lit.
● Is the power cord disconnected? Please confirm that the power cord is
securely connected to the power port.
● Is the switch used in an environment with temperature between 0 and 50
℃ ?
Use the switch within the range of the operating temperature.
The port LED is not lit.
● Is the cable correctly connected to the target port?
● Is an appropriate cable used?
● Does the terminal connected to the target port support 10BASE-T,
100BASE-TX, or 1000BASE-T?
● Auto-negotiation may have failed.
Set the port of this switch or the terminal to half-duplex mode.
◆ Communications are slow.
● Are the communication speed and mode settings correct?
When an appropriate communication mode signal cannot be properly
obtained, the switch operates in half-duplex mode.
Recheck the auto-negotiation settings.
● Is the bandwidth usage rate of the network to which this switch is con
-
nected excessively high?
Try separating this switch from the network.
◆ Communications fail.
● Are the ports linking up?
When the power saving mode or EEE (IEEE802.3az, Energy Efficient Ethernet
function) is enabled, the ports may not link up depending on the connected
devices.
Change the settings as follows.
1. Change the power saving mode settings to "Half" or "Disabled."
2. Change the EEE (IEEE802.3az) settings to "Disabled."
◆ PoE power supply is impossible.
Power is not supplied to a PoE power receiving equipment.
● When STP cables are used, power may not be supplied by PoE depending
on the installed environment. In such a case, use UTP cables.
● Is the cable used a CAT5e or higher straight cable (8P8C)?
● Is the cable correctly connected to a port that supports PoE power supply?
● Is the single port or the whole unit overloaded?
● Is the PoE power receiving equipment connected to the port compliant
with the IEEE802.3at or IEEE802.3af standard?
The port LED (right) is green blink.
● Is the amount of power requested by the PoE power receiving equipment
for the whole unit exceeding the maximum amount of power this switch
can supply?
For the maximum amount of power this switch can supply, refer to Section
5.2.11.
7. Troubleshooting
