Diesel engine instrumentation

Abstract The instrumentation system for a single-cylinder Bamford diesel engine installed in the Department of Engineering at the University of Reading is described. The system consists of an Apple II microcomputer with a single disc drive and 48 kbyte RAM, an instrumentation interface unit (IIU) and a variety of transducers. Transduction of the primary measurands into a form suitable for interfacing to the computer is dealt with first. Problems encountered are described and transducer choice is considered within constraints of a tight budget and measurement parameters. The instrumentation interface unit is described next. A modular approach is adopted throughout and the operational characteristics of the interface modules are discussed. The single cable connection to the Apple II allows the computer to be removed with minimal disruption and to be used for other purposes. Finally, the software designed to run the instrumentation interface unit and to interact with the user is described. The aim throughout has been to make the system single-keystroke-driven wherever possible and easy to use. The software has been structured and documented to allow easy maintenance and modification. The design procedure is discussed in some depth.