Safety of transformers, reactors, power supply units and combinations thereof. General requirements and tests|Fire tests, Torque, Electrical insulation, Drop tests, Switches, Cut-out devices, Clearance distances, Resistance measurement, Flexible conductors, Single-phase transformers, Portable, Temperature-rise limit, Overload protection, Safety measures, Electrical testing, Power transformers, Electrical safety, Power output, Electric enclosures, Impact testing, Protected electrical equipment, Dielectric-strength tests, Polyphase transformers, Small-power transformers, Alternating-current transformers, Tracking tests, Stationary, Safety isolating transformers, Environmental testing, Corrosion tests, Classification systems, Short-circuit current tests, Electric power systems, Cable glands, Electrical protection equipment, Leakage paths, Thermal testing, Symbols, Electrical equipment, Transformers, Dielectric strength, Electric terminals, Dry-type transformers, Rated frequencies, Marking