The PLC programming environment may be dedicated terminal or a PC (Personal Computer). Today due to their falling costs and increasing sophisticated they are to be found in the smallest production environment. Latterly, with the event of the programming language defined by IEC 612131 the PC is the favoured programming environment. LL (Ladder Logic) is now the most popular language. There is anecdotal evidence that the other defined languages are gaining acceptance slowly.
As the PLC is part of an automated system there are several modules that should be prerequisite, or be included, in any course. Those modules are electrical design, software engineering, and in some cases, mechanical design. Electrical design encompasses electrical panel construction and design to the relevant standard. Software engineering includes applying a SLDC (Software Development Life Cycle) approach to the system being designed and the ability to write the control program. The PLC apart from being run as a “stand alone” course is currently an integral part of courses ranging from agricultural engineering to mechatronics and industrial automation.
PLC courses, as for all control engineering course, must deliver a balance theoretical knowledge and practical skills, and as such are laboratory based. Increasing the response of demands from industry PLC courses are being run in house, in training rooms and away from the traditional venue of the automation laboratory using hardwired kits and PC based simulators.
The goals of the new proposed training system are that it must support the sub disciplines of computer programming, software engineering and panel wiring. While the basic system must support digital I/O it should be expandable to support analogue handling and non proprietary networking. The detailed objectives must:
• Be portable.
• Be safe.
• Be low costs.
• Fit Comfortably.
• Incorporate an industrial standard PLC.
• Interfaces to a PC.
• Support Ladder Logic languages programming.
• Be expandable to facilitate Ethernet networking.
• Be expandable to facilitate analogue handling.