Korenix JetNet 4000, User Manual

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Korenix JetNet 4000 Series Industrial Web-Managed Ethernet Rail Switch User’s Manual 4-2
Note : make sure you are using the correct VDC power suppliers (12 to 48 VDC) or power
adapters. Do not use power adapters with DC output over 48V. It will damage devices.
Note : select Ethernet cables with specifications suitable for your applications to set up your
systems. Ethernet cables are categorized into unshielded twisted-pair (UTP) and shielded
twisted-pair (STP) cables. Category 3, 4, 5 Ethernet cables are suitable for systems with 10
Mbps transmission speed. For systems with 100 Mbps transmission speed, Category 5 Ethernet
cables are the only suitable specifications for this environment. You also need to make sure that
the distance between each node cannot be longer than 100 meters (328 feet).
Note : if the power LED goes off when the power cord is plugged in, a power failure might occur.
Check the power output connection to see if there is any error at the power source. If you still
cannot solve the problem, contact your local dealer for assistance.
Note : use unshielded twisted-pair (UTP) or shield twisted-pair (STP) cables for RJ-45
connections. 100
Ω
Category 3, 4 or 5 cables are for 10Mbps connections, and 100
Ω
Category
5 cables are for 100Mbps connections. You also need to be sure that the length of any
twisted-pair connection does not exceed 100 meters (328 feet). Gigabit ports should use Cat-5
or cat-5e cables for 1000 Mbps connections. The length does not exceed 100 meters.
Incorrect Connections
The ports on the JetNet can auto detect straight or crossover cables when you connect the
JetNet with other Ethernet device. For the RJ-45 connectors, use correct UTP or STP cables.
For 10/100 Mbps ports, use 2 pairs of twisted cables, and 4 pairs of twisted cables for Gigabit
1000T ports. If the RJ-45 connectors and the cables are not correctly connected, the link will fail.
For fiber connection, make sure that the fiber cable mode should match the fiber module.
Faulty or Loosen Cables
Look for loosen or obviously faulty connections. If no such errors are found, make sure the
connectors and the cables are tightly connected. If that does not correct the problem, try a
different cable.
Non-standard Cables
Non-standard and incorrectly-wired cables may cause numerous network collisions and other
network problems, and can seriously impair network performance. A category 5 cable tester is a
recommended tool for every 100Base-T network installation.
Improper Network Technologies
It is important to make sure that you have a valid network topology. Commonly-made topology
mistakes include excessively long cable length and too many repeaters (hubs) between end
nodes. In addition, you should make sure that your network topology contains no data path loops.
Between any two end nodes, there should be only one active cabling path at any time. Data path
loops will cause broadcast storms that will severely impact your network performance.
LED Indicators
The JetNet can be easily monitored via the LED indicators located on the JetNet front panel to
assist in identifying common problems and to help you find possible solutions.
If the power LED indicator does light on when the power cord is plugged in, you might have a
problem with power outlet, or power cord. However, if the JetNet powers off after running for a
period of time, check for loosen power connections, power losses or surges at power outlet. If
you still cannot resolve the problem, contact your local dealer for assistance.