The IA 130 can be used to perform basic exercises on a PLC (programmable logic controller). A PLC is essentially a computer adapted to the needs of industry. Its inputs and outputs are not designed for humans, but for use in the control of machines. Machine and operator interact solely by way of limit switches, momentary-contact switches or photoelectric switches. The front panel is built as a laboratory patch board, where the input ports and output ports of the PLC can be connected to switches and displays via laboratory cables. In order to write programs the PLC must be connected to a PC (not supplied) via an RS232 interface.
The PLC programming software conforms to the international standard IEC 61131-3, and permits programming in the following languages: Statement List (STL), Ladder Diagram (LD), Structured Text (ST) and Function Block Diagram (FBD). Ladder Diagrams are based on graphical representations with contacts, coils and boxes, as per the circuit diagrams. Function Block Diagram language is based on graphical representation of the interlinking of logical function blocks, analogous to the logic diagrams. Statement List is an assembler-type language with a small, standardized non-hardware-dependent command set. Structured Text is a language similar to PASCAL, with mathematical expressions, assignments, function calls, iteration, condition selection, and PLCspecific add-ons. An example program is included in the module. IA 130 can be used as a control element in conjunction with electrical, pneumatic or hydraulic applications, such as with the handling device IA 210 or the mixing process RT 800.
The good-structured instructional material sets out the fundamentals and provides a step-by-step guide through the experiments.
• Familiarization with a PLC
• Familiarization with the essential fundamentals such as
a. Boolean algebra
b. compiling statement lists
c. interconnection diagrams and block diagrams
• Exercises in
b. logical "AND" / "OR" gates
c. logic relays
d. output and input
• Configuration of program sequences by way of connectors, incorporating
c. cascade circuits
d. Higher-order monitoring relays etc.
• Fault finding