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RS-485 Wiring
Notes:
1.
Usually, you have to connect all signal grounds of RS-422/485 devices together to reduce common-mode
voltage between devices.
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.
