INSTALLATION

The THN-MIM7593 does not report false collisions to the IRM. However, if a non-Cabletron Systems Ethernet device is connected to the segment, it is possible for false collisions to be generated. Non-Cabletron System devices should be thoroughly tested before using them with the THN-MIM7593.

2.2.3Thick-net Segments

50 ohm Ethernet type coaxial cable must be used when making up thick-net cable segments.

Each thick-net cable segment connected to a THN-MIM module must be no longer than 500 meters (1640 feet) in length.

When making up networks requiring shorter cable runs, Ethernet standard length 23.4, 70.2, and 117 meter cable sections should be used. These cable sections may be connected together by a barrel connector to form a cable segment.

Use of non-standard cable lengths may result in impedance mismatches causing reflections to occur. These reflections may cause data errors.

A 50 ohm terminator must be connected to the far end of the thick segment.

A BNC to N-Series adaptor must be connected to the applicable BNC port to attach the thick-net segment to the module.

A maximum of 100 transceivers may be attached to a thick-net cable segment, and these transceivers must be at least 2.5 meters apart throughout the length of the cable. Transceivers should be placed on the black bands that run along the cable that are marked at 2.5 meter intervals.

For safety, only one end of a thick-net segment should be connected to earth ground. Connection to earth ground at more than one point on the segment may allow for the occurrence of dangerous ground currents. The BNC ports of the THN-MIM are connected to earth ground. This eliminates the need for grounding a thick-net segment connected to the module.

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Cabletron Systems THN-MIM manual Thick-net Segments