They have been translated into ladder logic from switches and relay contacts used in electric circuits.Īn coil in ladder logic is the symbol which mainly defines PLC digital outputs. In ladder logic the normally open contact (NO) and normally closed contact (NC) symbols are mainly used to define PLC digital inputs and internal logic instructions.
While digital outputs are expressed as a coil symbol. Digital inputs are expressed as normally open contact (NO) symbols or normally closed contact (NC) symbols. The main symbols for PLC ladder logic are the input symbols and output symbols.
As your desire to program complex automation and process control Functions increases, then higher level ladder logic symbols can be used like math operations, PID loops, data manipulation and data conversion. Generally speaking a large majority of real world applications can be accomplished with the basic ladder logic symbols. Learning the basic ladder logic symbols will give you a solid foundation. Traditionally, ladder logic symbols were created for bit logic operations, but now include higher level functions such as timers, counters, math, comparison, PID loops, data manipulation and data conversion. In PLC programming, ladder logic symbols can be used individually or in combination to create logic instructions. Ladder logic symbols are the fundamental programming components used in ladder diagrams. If not, don’t worry, ladder logic is a graphical programming language and getting to know the basic ladder logic symbols and concepts is quite easy. If you have a basic knowledge of electric circuits then getting started in ladder logic programming should be a breeze.
The ladder logic symbols that are used in PLC programming have been derived from traditional relay logic control circuits.
0 kommentar(er)
