JFET_V3_N4_RP2 S.M. Rizwan Gulshan Taneja Vipin Khurana Ahmed Mohiuddin Journal on Future Engineering and Technology 2230 – 7184 3 4 19 26 Programmable Logic Controller (PLC), Failures, Repairs, Semi-Markov process, Regenerative point Many industries are operated and controlled by Programmable Logic Controller. A reliability analysis of such an industrial system, along with a very practical concept of inspection for detecting the type of failure is introduced in this paper. The real data of one of the PLC controlled manufacturing unit have been used for various failure, inspection, repair, replacement and reinstallation rates. Thus, the whole situation is embedded into a model where a single unit PLC system with four types of failure is analyzed and important reliability indices are obtained. Furthermore, semi-Markov processes and regenerative point techniques are used in obtaining the reliability indices. Profit incurred to the system is also evaluated. The particular case is examined graphically. May - July 2008 Copyright © 2008 i-manager publications. All rights reserved. i-manager Publications http://www.imanagerpublications.com/Article.aspx?ArticleId=600