Small-capacity capacitor measurement method

The capacitance of a small-capacity capacitor is generally 1 UF or less, because the capacity is too small, the charging phenomenon is not obvious, and the deflection of the hands to the right during measurement is not large. Therefore, with a multimeter, it is generally impossible to estimate its capacitance, but only to detect whether it is leaking or breakdown. When normal, use the multimeter to measure the resistance value of both ends of the multimeter R×10 k block to be infinite. If a certain resistance is measured or the resistance is close to 0, the capacitor has been leaked or has broken down.

During the measurement, connect the black and red ends of the circuit to the black and black pens of the multimeter. For capacitors below 2200pF, they can be connected between the 1st and 2nd ends of the circuit. For capacitors larger than 2200pF, they can be connected between the 2nd and 3rd ends of the circuit. By observing the amplitude of the right hand swing of the forward and backward measurements, it can be judged whether the capacitor is invalid (similar to the determination method when measuring the electrolytic capacitor).

According to the nominal capacitance of the measured capacitor, select the appropriate capacitance range CAP, plus 2μ file (the table has 2000pF, 20nF, 200nF, 2μF, 20μF and other 5 files), adjust the zero knob (only for measuring capacitors), Let the initial value (ie, the no-load capacitance value, the value displayed on the display screen before the capacitor is inserted) be “000” or “-000”, and then measure the capacitor C. Insert the digital multimeter CAP socket, the multimeter display immediately shows the value of the measured capacitor.