Cabletron Systems STH-22, 42, 24 General Considerations, Temperature, Installation Recommendations

General Considerations

to re-route cabling away from potential noise sources, or to ensure that the electrical wiring in the area is properly wired and grounded, or to replace connectors along affected segments.

Temperature

The attenuation of PVC-insulated cable varies significantly with temperature. Check the cable manufacturer’s specifications. Plenum- rated cables are strongly recommended in areas where temperatures exceed 40˚C. Under such conditions, plenum-rated cables ensure that cable attenuation remains within specifications.

Installation Recommendations

In addition to complying with the cable specifications presented in Sections 2.2 and 2.3, the cabling installation should comply with the following recommendations to obtain optimum performance from the network:

•UTP cabling should be free of splices, stubs, or bridged taps.

•No more than two punch-down blocks should exist between TCU ports and wall outlets.

•Metal troughs, ducts, etc. carrying Token Ring signals should be properly grounded.

•Cables should be routed away from sources of electrical noise, such as power lines, fluorescent lights, electric motors, radio interference, and heavy machinery.

•Token Ring signals should not be routed through UTP cables that exit a building or which are adjacent to cables either exiting a building or exposed to lightning strikes and power surges.

•UTP cables that contain Token Ring signals should not be simultaneously used for applications which may impress high voltages (greater than 5 volts) with sharp rise or fall times, since the noise coupling from such signals could directly cause errors on the Token Ring network.

•For single telecommunications closet rings, lobe lengths should not exceed 100 meters of 22 to 24 AWG wire from the attaching device and the TCU port.

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