Instrument/electrical preventive maintenance includes calibration, testing, installation, troubleshooting, and repair of plant equipment, such as process control devices, motors, generators, batteries, transformers, regulators, valves, circuit breakers, disconnecting switches, analog/digital instrumentation, control relays, communication systems, lighting, and auxiliary equipment within the generating station and associated substations. Mechanical preventive maintenance includes calibration, testing, installation, troubleshooting, and repair of equipment such as aero-derivative turbines, generators, clutches, motors, pumps, compressors, and auxiliary systems.