Circuit for simultaneous testing electrometers with connected voltage and current circuit

摘要

Circuit arrangement for simultaneous testing of electricity meters with inter connected current and voltage measurement circuits comprising a plurality of said meters all having voltage terminals associated with the same phase connected in parallel to a respective voltage source and each of the current terminal pairs of the meters being connected to the output of an individual zero flux current transducer. The inputs of the zero flux current transducer, the outputs of which are associated with the same phase of the individual meters, are connected in series to a respective current source. The zero flux current transducer consists of an input winding, an output winding, a sense winding, a drive winding, a sense core, a drive core and an amplifier. The drive winding comprises the drive core only and the input, output and sense windings comprise both sense core and drive core. The sense winding is connected to a high impedance input of the amplifier and the drive winding is connected to a low impedance output of the amplifier.