Contemporary Control Systems EXP Expansion Modules User Manual - Manual (Page 13)

RG-59/u cable. We recommend RG-62/u because it is a better
match to the transceivers and a full 2000 foot segment distance
can be achieved using this cable. Both cables support male BNC
connectors which the -CXS expansion module accommodates.
2.5.2 Connecting Coaxial Cable Bus Networks (-CXB)
There is no expansion module for a bus transceiver (-CXB);
however, bus topology is supported with the MOD HUB. In a
bus configuration, one end of the segment terminates into a
-CXS expansion module without a passive terminator.
However, the other end of the bus segment is terminated with a
passive terminator. Be sure to use the proper passive terminator,
93 ohms for RG-62/u and 75 ohms for RG-59/u. Do not attach
the -CXS expansion module in the middle of a bus segment
using a BNC “T” connector. However, the same effect can be
accomplished by splitting the bus segment into two pieces, each
of which attaches to a -CXS port. Again, no passive termination
needs to be applied to the hub side of a bus segment.
2.5.3 Connecting Twisted-Pair Star Networks (-TPS)
Each -TPS port is constructed as a -CXS port with an internal
BALUN transformer. A BALUN (which is an acronym for
BALanced-UNbalanced) connects the single-ended -CXS
transceiver to a balanced transceiver suitable for driving
balanced twisted-pair cabling. The internal BALUN in the -TPS
port is compatible in wiring to an external MUX LAB's part
number 10070 BALUN. Therefore, a -TPS port can directly
connect to another -TPS port on either a hub or a NIM or
connect to an external BALUN attached to a -CXS port. In both
cases use straight-through twisted-pair cable with
RJ-11
connectors. Straight-through cable provides a one to one
correspondence in cable connections at both ends. Straight-
through cable can be identified as follows. Take both connectors
from a cable length and lay them side by side with the locking
clip facing the same direction. The wire color present on the
left-most side of one connector must be the same color on the
TD401600-0M
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