Rockwell Automation 1770 DH,DHII,DH485 CABLE - Manual (Page 113)

Appendix
A
A-1
Constructing RSĆ232ĆC and Longline Cables
Appendix A provides information on what types of adapter cables to use when
connecting node interface modules to their host processors and to other
communication interface modules. Where practical, we provide a wiring
diagram so that you can make your own cable.
We discuss two types of connections to node interface modules:
RS-232-C connections (less than 50 cable feet or 15.3 meters)
longline connections (up to 7,000 cable feet or 2135 meters)
Most of the input and output circuits on node interfaces conform to RS-232-C
electrical specifications.
Chapter Overview
RSĆ232ĆC Connections
(Less than 50 Cable Feet)