Rs-422 Wiring; Rs-485 Wiring - ICP DAS USA tDS-722 User Manual

Tiny Serial-to-Ethernet Device Server

2.7.2 RS-422 Wiring

2.7.3 RS-485 Wiring

1. Usually, you have to connect all signal grounds of RS-422/485 devices together to
reduce common-mode voltage between devices.
Note
2. Twisted-pair cable must be used for the DATA+/- wires.
3. Both two ends of the cable may require a termination resistor connected across the
two wires (DATA+ and DATA-). Typically 120 Ω resisters are used.
4. The Data+ and B pins are positive-voltage pins, and Data- and A pins are negative-
voltage pins in the above figure. The B/A pins may be defined in another way
depending on devices, please check it first.
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