M251 PLCSystem Library Guide

M251 PLCSystem Library Guide

This document acquaints you with the system functions and variables offered within the Modicon M251 Logic Controller. The M251 PLCSystem library contains functions and variables to get information and send commands to the controller system.

This document describes the data types functions and variables of the M251 PLCSystem library.

The following basic knowledge is required:

oBasic information on functionality, structure, and configuration of the M251

oProgramming in the FBD, LD, ST, IL, or CFC language

oSystem variables (global variables)