3Com 3CNJPSE24, User Manual

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Appendix C — Troubleshooting
C-4 Ethernet Power Supply User s Guide
Problem Resolution
The end device
operates, but
there is no data
link. Verify that:
•
The Port LED on the Ethernet Power
Supply front panel is lit continuously.
•
The "Data" and "Data & Power" ports
correspond.
•
If an external splitter is in use, replace
it with a new splitter. Discard the
faulty splitter.
•
You are using a standard UTP
Category 5 cable, including all 8 wires
(4 pairs), and is 100m or less in
length between the switch and the
end device.
•
You are not using any crossover
twisted pair wires.
•
The Ethernet Power Supply is
connected to a switch or hub with a
good RJ-45 patch cord connection.
In addition, try to:
•
Bypass the long twisted pair cable
and bring the end device close to the
Ethernet Power Supply and connect
to one of the ports using a short
cable. If this works, there is probably
a faulty connection or short on the
long cable, or one bad RJ-45
connection along the line.