Contemporary Research TD960801-0MC - Manual (Page 16)

TD960801-0MC
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2.6 Connecting to the Backbone Port
The backbone (link) port is ARCNET compliant and, therefore,
complies with the cabling rules for ARCNET networks. For
more information on designing an ARCNET cabling system,
refer to Contemporary Controls’ publication, “ARCNET
Tutorial & Product Guide.”
Either of two transceivers are available on the backbone port.
The coaxial bus (-CXB) transceiver requires coaxial cable
allowing a total of eight EXTEND-A-BUS devices to be
connected onto one wiring segment. The fiber optic (-FOG)
transceiver allows for two EXTEND-A-BUSes to be connected
in a point-to-point or link fashion. If star or distributed star
topologies are desired or if the cabling distances must exceed the
basic specifications, ARCNET compliant active hubs are
required. Contemporary Controls provides two series of active
hubs–the MOD HUB series of modular hubs and the AI series
of fix port hubs. Refer to the appendix for more information on
active hubs.
2.6.1 Connecting Coaxial Bus Networks (-CXB)
Coaxial bus backbone ports must be interconnected with
RG-62/u 93-ohm coaxial cable. In a simple two EXTEND-A-
BUS arrangement, a BNC-Tee (BNC-T) is twisted onto each
BNC backbone port. A length of RG-62/u cable, no shorter
than 6 feet (2 m) nor longer than 1000 feet (305 m) is connected
between the BNC-Tee connectors. At the open end of each
BNC-Tee is connected a 93-ohm terminator (BNC-TER). This
completes the basic connection.