User manual

Publication LOGIX-AP010B-EN-P - May 2010 49
Software Conversions - Program Structure Chapter 2
RSLogix 5000 Ladder Diagram
Traditionally, Ladder Diagram is used for implementing Boolean
combinational logic. In RSLogix 5000 software, it can also be used for
sequential logic, motion, data manipulation, and mathematical calculations,
although other languages may be more convenient for these tasks.
RSLogix 5000 Structured Text
Structured Text is a high level procedural language that is similar in structure
to Visual Basic, Pascal and C. It is used primarily for data manipulation and
mathematical calculations, although motion, combinational, and sequential
logic can also be programmed in Structured Text.
RSLogix 5000 Function Block Diagram
Function Block Diagram describes graphically a Boolean or mathematical
function relating input variables and output variables. Input and output
variables are connected to blocks by connection lines. An output of a block
may also be connected to an input of another block.
It is a good practice to program PID loops in FBD. It is the most convenient
language for process control.
RSLogix 5000 Sequential Function Chart
SFC is a graphical tool for describing sequential logic as a set of states and
transitions. Outputs may be assigned to a state, and conditions with Boolean
results for transitions to other states defined.