Process, appliance and probe for measuring an electrical triphase system using an oscilloscope

摘要

To be able to measure an electrical three-phase system with respect to the amplitude of its currents or voltages and with respect to the phase shift between currents and voltages by means of conventional oscilloscopes, the invention provides for converting the three-phase system into a two-phase system and to apply its two phases to the horizontal and vertical deflection input of the oscilloscope and to check a voltage phase in the case of the measurement of the current phases and a current phase in the case of the measurement of the voltage phases of the three-phase system for the occurrence of a predetermined phase angle and, every time this phase angle is detected, to generate a marking pulse which is applied to a brightness or colour control input of the oscilloscope. As a result, a circle is displayed on the oscilloscope when the amplitudes of the three phases are of equal magnitude and on the circle a mark of varying brightness or colour is displayed, the radius of the circle corresponding to the amplitude and the angular position of the mark corresponding to the phase shift between voltage and current of the three-phase system. IMAGE