This course in mechanical devices and systems is one of 16 courses in the Energy Technology Series developed for an Energy Conservation-and-Use Technology curriculum. Intended for use in two-year postsecondary technical institutions to prepare technicians for employment, the courses are also useful in industry for updating employees in company-sponsored training programs. Comprised of eight modules, the course is an in-depth study of the principles, concepts, and applications of various mechanisms that may be encountered in industrial application of energy use and conservation. Operational procedures, uses, maintenance, troubleshooting, and repair and replacement procedures are covered. The application portions of the modules emphasize practical maintenance and installation of equipment and specification of proper replacement components for manufacturers' catalogs. Written by a technical expert and approved by industry representatives, each module contains the following elements: introduction, prerequisites, objectives, subject matter, exercises, laboratory materials, laboratory procedures (experiment section for hands-on portion), data tables (included in most basic courses to help students learn to collect or organize data), references, and glossary. Module titles are Belt Drives, Chain Drives, Gear Drives, Drive Train Components I and II, Linkages, Fans and Blowers, and Valves. (YLB)