Novel test methods applicable to periodic inspection of mine electrical systems and components were investigated. Several classes of test, such as power factor measurement on unloaded lines and infrared inspection, show promise of providing early warning of equipment failure. Transient analysis programs were developed to process data expected to be available from a Pennsylvania State University Field Survey under Grant No. Go155003. A ground bed monitor that provides a continuous record of bed impedance was developed. Research on circuit breakers and protective devices included development of a computer program to verify correct settings of haulage circuit breakers, based on rail and feeder size, lengths, etc., as entered interactively at a teletype terminal.