Abstract: This invention relates to a voltage sensor for sensing a voltage on an electrically charged object such as a distribution line or the like, the sensor being disposed with an insulation space to the object. The voltage sensor includes an amplifier circuit for outputting a signal having a waveform similar to that of a displacement current inflowing from the electrically charged object via the insulation space, and a filter circuit for extracting a signal having predetermined frequencies from the output of the amplifier circuit and outputting an alternating current waveform similar to the potential of the electrically charged object.

Abstract: This invention relates to a voltage sensor for sensing a voltage on an electrically charged object such as a distribution line or the like, the sensor being disposed with an insulation space to the object. The voltage sensor includes an amplifier circuit for outputting a signal having a waveform similar to that of a displacement current inflowing from the electrically charged object via the insulation space, and a filter circuit for extracting a signal having predetermined frequencies from the output of the amplifier circuit and outputting an alternating current waveform similar to the potential of the electrically charged object.

Abstract: An overcurrent condition display suspended directly from a distribution cable for displaying overcurrent conditions in the cable and for promptly locating spots of accidents due to overcurrent conditions comprises a current sensor section having a current transformer, a drive section provided with a drive element adapted to be driven by the sensed overcurrent and with a force storage member adapted to be actuated by the drive element and to act as a restoring member as well for the drive element, a drive-transmission section actuated by the force storage member and a display section having a display tube with a transparent bottom, a viscous fluid stored in the tube and a display element connected to the drive-transmission section for vertical motion through the fluid. The overcurrent condition is displayed when the display element is hoisted by the drive-transmission section.