Resistance welding water-cooled transformers of the press-package and portable types. Specification for portable transformers|Electrical resistance, Rated voltage, Welding equipment, Ratings, Water-cooled systems, Short-circuit current tests, Electrical insulation, High-voltage tests, Electrical testing, Testing conditions, Thermal testing, Environment (working), Transformers, Performance testing, Resistance-welding equipment, Type testing, Portable, Grades (quality), Rated current, Protected electrical equipment, Temperature-rise limit, Single-phase transformers, Earthing, Marking