ELECTRONIC ELECTRICITY METER Russian patent published in 1995 - IPC

FIELD: measuring devices. SUBSTANCE: primary current and voltage converters 2 and 3 are connected to multiplier 4 whose output is connected via frequency-pulse converter 7 with reading device 10 and, via amplitude value converter 6, second threshold element 9 and time delay unit 11 with the second input of OR element 12. The output of the primary current converter is connected across rectifier 5 and first threshold element 8 with the first input of OR element 12 whose output is connected to the control input of an automatic switch whose power circuit is cut in in-series with load 1. Temporary disconnection of the meter under overloads promotes its reliability. EFFECT: improved design. 2 dwg