IsaGRAF1

What is ISaGRAF?

Implementation of Control Microsystems ISaGRAF enables the programming of SCADAPack controllers using the IEC 61131-3 programming languages. The programming environment uses the ISaGRAF Workbench to create, load and debug IEC 61131-3 application programs.

ISaGRAF Workbench supports the five standard IEC 61131-3 programming languages, and a sixth language called Flow Chart. These languages may be intermixed within an application to provide an optimum control strategy. The six supported programming languages are:

Sequential Function Chart (SFC). The Sequential Function Chart is a graphic language used to describe sequential operations in a process. The process is graphically partitioned into a set of well-defined steps containing actions performed using other languages such as ST, IL, LD and FBD. Steps are linked together with conditional transitions. This language is useful for batch processes and process procedures such as automatic startup and shut down.

Functional Block Diagram (FBD). The Function Block Diagram is a graphic language used to build complex procedures from a library of functions. Standard library functions such as math and logic may be combined with custom library functions such as dial up modem control, HART Interface, PID controllers and Modbus master and slave protocols to create Function Block Diagram application programs. A class of programs called functions allows the creation of user functions that are not included in the library

Ladder Diagram (LD). Ladder Diagram is a graphic language combining contacts and coils to build logical discrete control procedures. This language is identical to the relay ladder logic used by most programmable Logic Controllers. Ladder Diagram contacts and coils may be used in the Function Block Diagram language for discrete control of functions.

Structured Text (ST). Structured Text is a high-level structured language, similar to Pascal and C, that is used for complex procedures or calculation that cannot be easily implemented using graphic languages. Structured Text is the default language used to describe actions within the steps of the Sequential Function Chart language.

Instruction List (IL). Instruction List is a low-level programming language, similar to assembly language that is used in small applications that require fast execution. This language is typically used to optimize sections of an application.
Flow Chart (FC). Flow Chart is a graphic language that is used to describe sequential operations in an application. A Flow Chart diagram is composed of actions to be performed and tests on the actions performed. Actions and tests are connected by oriented links, representing data flow through the Flow Chart. Tests determine the yes or no path of the data flow.