2018BS EN 62052-21:2004+A1:2017 Electricity metering equipment (a.c.). General requirements, tests and test conditions. Tariff and load control equipment
2005BS EN 62052-21:2005 Electricity metering equipment (a.c.) - General requirements, tests and test conditions - Tariff and load control equipment
2005BS EN 62052-21:2004 Electricity metering equipment (a.c.) - General requirements, tests and test conditions - Part 21: Tariff and load control equipment