37 Assembly, commissioning (putting into service), inspection, maintenance, repair and overhaul of power supply systems, electric networks and electric and technical systems and equipment, measuring equipment, control equipment, monitoring equipment, transformers, coils, switching devices, sensors, computers, on-load tap-changers on transformers and coils, motor-drives for on-load tap-changers on transformers and coils, and equipment for actuating, controlling, monitoring and testing transformers, coils, switching devices, electric networks and electric installations; assembly, commissioning (putting into service), inspection, maintenance, repair and overhaul of equipment for actuating, controlling, monitoring and testing on-load tap-changers on transformers and coils; assembly, commissioning (putting into service), inspection, maintenance, repair and overhaul of equipment for actuating, controlling, monitoring and testing motor-drives for on-load tap-changers on transformers and coils; assembly, commissioning (putting into service), inspection, maintenance, repair and overhaul of equipment for securing and improving the energy quality of public, private and industrial power supply systems, and installations for conducting, transforming, accumulating or controlling electric energy, power, current and voltage; assembly, commissioning (putting into service), inspection, maintenance, repair and overhaul of installations for influencing and controlling power supply systems and electric networks, and for securing and improving quality of supply in power supply systems and electric networks