| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide an AC power measuring device capable of keeping average power within the range of a desired detection error to measure the average power by using a voltage value of insulation electric wire detected in a non-contact manner by voltage detecting means and a current value detected by a current transformer. <P>SOLUTION: Probes 12R and 12S for making capacitance generated by electrodes 12R2 and 12S2 to be a value calculated in advance are arranged on outside surfaces of insulation coatings 11R2 and 11S2 of insulation electric wires 11R and 11S, respectively, and a current transformer 13R is arranged at the insulation electric wire 11R. A measuring instrument 20 for performing an arithmetic operation by using a detected AC voltage value and AC current value is provided and has at least a voltage detecting part 21 including a partial pressure resistance circuit including an input resistor and an output resistor connected to the probes 12R and 12S, and an operation amplifier circuit for performing operation amplification of a partial pressure voltage signal, a current detecting part 22 for detecting current of the current transformer, analog/digital converters 23 and 24 for respectively converting each signal, and an operation processor for calculating AC current on the basis of signals from the analog/digital converters 23 and 24. <P>COPYRIGHT: (C)2012,JPO&INPIT |
