AENOR UNE-EN 62052-21/A1:2017 Electricity metering equipment (AC) - General requirements, tests and test conditions - Part 21: Tariff and load control equipment
2017AENOR UNE-EN 62052-21/A1:2017 Electricity metering equipment (AC) - General requirements, tests and test conditions - Part 21: Tariff and load control equipment