ELECTRIC MEASURING, CALCULATING, CONTROLLING AND REGULATING APPARATUS, EQUIPMENT AND INSTRUMENTS FOR THE SUPPLY AND DISTRIBUTION OF ELECTRICAL ENERGY, NAMELY, SWITCHGEARS, OFF-CIRCUIT AND ON-LOAD TAP-CHANGERS ON TRANSFORMERS, ELECTRICAL CONTROLLERS FOR THE OPERATION, CONTROL, REGULATION, SUPERVISION AND TESTING OF SWITCHGEARS, OFF-CIRCUIT AND ON-LOAD TAP-CHANGERS ON TRANSFORMERS

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