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Figure-5
RS-485 Board Connectors & Jumpers
Full Duplex Wiring Configuration:
A full-duplex system, as illustrated in Figure-6, is the most straightforward configuration,
and offers the highest potential for data transfers as there is no latency in enabling and
disabling of transmitters. The downside here is the extra cost and larger cable size
associated with full-duplex wiring. Cabling is specified as two sets of twisted pair wire, a
common conductor, and a shield. In the marketplace it is easier to obtain a cable having 3
sets of twisted pairs, as opposed to a more specialized cable with 2 twisted pairs and a
common conductor. Therefore, it is more practical to simply use an entire twisted pair set
to serve as the signal common.
Figure-6
Point-to-Point Full Duplex Wiring
Note that Figure-6 is drawn to show the transmitter output TX-Y feeding into the receiver
input RX-A, and the TX-Z going into RX-B. Correct polarity of the cable connections is
