A combined measuring apparatus for the measurement of the resistor and the transmission ratio of transformers windings

摘要

A combined measurement device for automatic measurement of resistance and transfer ratio, in partic. of transformers, is designed to provide high accuracy measurements in a short ime and to be suitable for inclusion in an automatic test system. The device contains d.c. and a.c. sections. The d.c. circuit for resistance measurement contains a battery, current limiting and sensing resistors, and two amplifiers. The a.c. circuit for transfer ratio measurement contains two attenuating-to-direct current voltage convertors. The connection of the two circuits to a processor via a-d convertors is regulated by a control circuit and selectors. The processor sends calculated values to a digital display.