Capacitance measuring device using linear voltmeter - has transformer secondary winding connected via capacitor to bridge rectifier

摘要

The voltmeter permits measurement of capacity values with linear scale and avoids problems of providing logarithmic scale where a current measurement is employed. A mains protection transformer (1) has secondary winding connected via a capacitor being measured to bridge rectifier circuit (2). The current is rectified and flows through a resistor (3) across which a voltmeter (5) is connected to measure the voltage. A switch (4) permits selection of various sensitivities. These resistors are chosen to keep rectified voltage as small as possible.