| 摘要 |
<p>A switching arrangement in a static kWh meter with means (2, 3) for generating measuring signals proportional to the current and to the voltage, a multiplicator (1, 4) for forming the product of the measuring signals, a voltage/frequency converter (5) for converting the output of the multiplicator into a frequency signal (f), and a counting device (7) controlled by the frequency signal, displaying the energy consumed. In order to compensate for the offset voltage (Uos) of the operation amplifier (11) of the integrator in the voltage/frequency converter, the converter comprises a compensating circuit with first switch members (K1, K2) which allow the output of the multiplicator to be integrated during given sampling periods, and in the input circuit of the integrator a compensating capacitor (C2) in which the offset voltage (Uos) of the amplifier (11) is stored by the aid of second switch members (K3, K4) operating between the sampling periods.</p> |
