Rf Module Rs-485/422 Connection Guidelines - Digi XTend User Manual

RF module RS-485/422 connection guidelines

The RS-485/422 protocol provides a solution for wired communications that can tolerate high noise and push signals
over long cable lengths. RS-485/422 signals can communicate as far as 4000 feet (1200 m). RS-232 signals are suitable
for cable distances up to 100 feet (30.5 m).
RS-485 offers multi-drop capability in which you can connect up to 32 nodes. Use the RS-422 protocol for point-to-
point communications.
To integrate the product model with the RS-485/422 protocol, we suggest the following:
1. When using Ethernet twisted pair cabling: connect T+ and T- to each wire in a twisted pair. Likewise, connect R+
and R- to a twisted pair. For example, tie the green and white/green wires to T+ and T-.
2. For straight-through Ethernet cable (not cross-over cable), the following wiring pattern works well: Pin 3 to T+, Pin
4 to R+, Pin 5 to R-, Pin 6 to T-.
3. The connecting cable only requires 4 wires, even though there are 8 wires.
4. When using phone cabling (RJ-11), Pin 2 in the cable maps to Pin 3 on the opposite end of cable and Pin 1 maps to
Pin 4 respectively.
XTend RF Module User Guide
RF module RS-485/422 connection guidelines
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