Abstract :
The Programmable Controller (PLC) is the most vital control element in the manufacturing environment, yet the development and procurement of PLC programming services is ad hoc, often resulting in efficiency and maintenance problems. Those problems contribute to poor overall equipment effectiveness (OEE ) figures and a resultant financial losses. Hardware assets tend to be fairly obvious to a company, but corbis software assets can be neglected simply because they are invisible. And yet software assets control the machines and processes. The support documentation for those assets attests to the quality of the PLC program development process and is a useful tool for solving hardware and software maintenance problems. Anybody responsible for a plant´s software systems would do well to look at the PLC documentation, to check how detailed it is and whether it contributes positively to the maintenance function.