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The tan twisted pair represents the second channel on the bus. For the tan channel, activate the termination resistor on the slave at the remaining end of the bus (slave station n in the diagram below). At least one slave station must have its biasing resistors activated. For redundancy it is recommended to active two slave station RS-422 biasing (no more then two should be activated).
RS-422 Network Topology
For RS-422 mode, place the RS-422 ON/RS-485 OFF switch to the ON position (to the left).
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