Performs basic electrical work by replacing faulty switches, sockets, plugs, fuses, breakers, insulators and other simple elements of electrical systems, fixtures and equipment, installing new conduits, wiring, and electrical machinery, inspecting and testing electrical lighting, power circuits, and equipment. Performs skilled mechanical maintenance work in the installation, operation, maintenance, modification, service and repair of electrical, HVAC and fire control systems by inspecting and testing elements of those systems to locate and diagnose faults and malfunctions.