Abstract: An energy consumption meter having a variable phase error compensator. While the variable phase error compensator may provide fixed phase error compensation for fixed phase error(s), it may also provide variable compensation for varying phase error(s) introduced by one or more parameters. Varying phase error(s) may be introduced, for example, by fluctuations in the frequency of an alternating current supply. Such varying phase errors may be corrected by monitoring one or more sources of varying phase error(s), calculating one or more appropriate corrections, and correcting one or more sampled parameters involved in determining energy consumption. This avoids erroneous energy consumption metering due to varying phase errors.

Abstract: An electric energy meter (1) for an AC mains supply providing an AC mains voltage has a DC tolerant current transformer (6). A primary conductor of the transformer is connected to the AC mains supply and to a load (4). A secondary winding inductively produces a secondary voltage. An inherent transformer phase error exists between the currents in the primary conductor and the secondary voltage. The meter has first sampling means connected to the primary conductor for obtaining a first series of samples (Un, n=1, 2, . . . ) representative of the AC mains voltage and second sampling means connected to the secondary winding for obtaining a second series of samples (In, n=1, 2, . . . ) representative of the secondary voltage. The meter also has calculating means for obtaining a phase corrected series of samples by applying a phase shift correction compensating the transformer phase shift (?CT) to each sample from said second series of samples (In, n=1, 2, . . . ).

Abstract: In the resistance measuring circuit, a measuring capacitor (Cm), as controlled by a microcomputer (10), is charged in a first cycle to a predefined charging voltage (Vcc) and discharged via a reference resistor (Rref) to a predefined discharge voltage before then being recharged in a second cycle to the charging voltage and discharged via the resistance to be measured (Rs1) to the discharge voltage. The microcomputer (10) measures in each cycle the time duration between the start of the discharge procedure and the point in time of attaining a predefined fixed value of the voltage between the charging voltage and the discharge voltage across the measuring capacitor (Cm). From the product of the reference resistance and the ratio of the time duration measured in the second and first cycle, the resistance value to be measured is determined. There is provided a closed loop (10, 14, 16) for controlling the discharge voltage to a fixed predefined constant value.

Abstract: Procedure for the determination of the consumption of electrical energy by a consumer in a procedure for the determination of the consumption of electrical energy by a consumer, the sinusoidal alternating voltage applied to the consumer and the sinusoidal alternating current flowing to the consumer are measured at points in time which correspond to a pre-determined sampling rate. Products are formed of the values measured, and the products are added together for the duration of the energy consumption by the consumer. For each voltage value measured at a voltage-measurement point in time, in accordance with the timing interval of the sampling period, current values are measured at points &Dgr;t before the voltage measurement point in time and at &Dgr;t after the voltage measurement point in time.

Abstract: In the resistance measuring circuit, a measuring capacitor (Cm), as controlled by a microcomputer (10), is charged in a first cycle to a predefined charging voltage (Vcc) and discharged via a reference resistor (Rref) to a predefined discharge voltage before then being recharged in a second cycle to the charging voltage and discharged via the resistance to be measured (Rs1) to the discharge voltage. The microcomputer (10) measures in each cycle the time duration between the start of the discharge procedure and the point in time of attaining a predefined fixed value of the voltage between the charging voltage and the discharge voltage across the measuring capacitor (Cm). From the product of the reference resistance and the ratio of the time duration measured in the second and first cycle, the resistance value to be measured is determined. There is provided a closed loop (10, 14, 16) for controlling the discharge voltage to a fixed predefined constant value.

Abstract: Procedure for the determination of the consumption of electrical energy by a consumer In a procedure for the determination of the consumption of electrical energy by a consumer, the sinusoidal alternating voltage applied to the consumer and the sinusoidal alternating current flowing to the consumer are measured at points in time which correspond to a pre-determined sampling rate. Products are formed of the values measured, and the products are added together for the duration of the energy consumption by the consumer. For each voltage value measured at a voltage-measurement point in time, in accordance with the timing interval of the sampling period, current values are measured at points &Dgr;t before the voltage measurement point in time and at &Dgr;t after the voltage measurement point in time.

Abstract: In a method for measuring the consumption of electrical energy by a consumer the momentary values of the alternating voltage and alternating current are measured alternately in the time spacing of a sampling cacle. Each measured momentary value is stored. From the momentary value measured in each sampling period and the stored momentary value the product is formed and the formed products added together. The sum of the products formed is then multiplied by a correction constant depending on the frequency of the alternating current and of the alternating voltage as well as on the sampling period.