Rockwell Automation 1747-L5xx SLC 500 Modular Hardware Style User Manual - Manual (Page 201)

201 Publication 1747-UM011G-EN-P - June 2008
Appendix
C
RS-232 Communication Interface
This appendix provides an overview of the RS-232 communication
interface and explains how the SLC 5/03, SLC 5/04, and SLC 5/05
processors support it. This appendix also provides information on:
• RS-232 and SCADA applications.
• RS-232 communication interface overview.
• SLC 5/03, SLC 5/04, and SLC 5/05 processors and RS-232
communication.
• SLC 500 devices that support RS-232 communication.
• DF1 protocol and the SLC 5/03, SLC 5/04, and SLC 5/05 processors.
• Modbus RTU Master communication.
• ASCII communication.
• DF1 communication protocol modems overview.
• wiring connectors for RS-232 communication.
• applications for the RS-232 communication interface.
For online configuration procedures of the SLC 5/03, SLC 5/04, and
SLC 5/05 processors for DF1 protocol, see your programming software
user manual.
RS-232 and SCADA
Applications RS-232 is a communication interface included under SCADA
(Supervisory Control and Data Acquisition) applications. SCADA is a
term that refers to control applications that require communication
over long distances. For more information about the use of
Allen-Bradley equipment in SCADA applications, refer to the SCADA
System Applications Guide, publication AG-UM008.
RS-232 Communication
Interface Overview RS-232 is an Electronics Industries Association (EIA) standard that
specifies the electrical, mechanical, and functional characteristics for
serial binary communication.
One of the benefits of RS-232 communication is that it lets you
integrate telephone and radio modems into your control system. The
distance over which you are able to communicate with certain system
devices is virtually limitless.