DIN EN 60051-5 E:2017-02 Direct acting indicating analogue electrical measuring instruments and their accessories; part 5: special requirements for phase meters, power factor meters and synchroscopes
1970DIN EN 60051-5 E:2017-02 Direct acting indicating analogue electrical measuring instruments and their accessories; part 5: special requirements for phase meters, power factor meters and synchroscopes
1991DIN EN 60051-2:1991 Direct acting indicating analogue electrical measuring instruments and their accessories; part 2: special requirements for ammeters and voltmeters (IEC 60051-2:1984, edition 4); german version EN 60051-2:1989