Almost any digital multimeter is suitable for measuring the capacitance of capacitors. Some of these devices allow you to measure capacitance directly, while others require resorting to indirect measurement methods.
Instructions
Step 1
To measure the capacitance of a capacitor with a multimeter that has the appropriate function, connect it to the capacitor, and then select the switch with the most accurate capacitance measurement range. If an overload message appears on the indicator, switch the device to a coarser limit. Continue this switch until the reading appears. Read them.
Step 2
If using a capacitance bridge, use a multimeter as a bridge balance device. Connect it to the corresponding terminals of the bridge through a detector with a filter capacitor, and on the multimeter itself, select the DC microammeter mode. Connect the capacitor to the bridge, balance the latter to the minimum reading, then read the reading on the bridge scale.
Step 3
If the multimeter does not have a capacitance measurement function, but there is no bridge attachment, use the following method. Take a standard signal generator. Set it to a known signal amplitude of several volts. Connect in series a multimeter operating in the microammeter or AC milliammeter mode (depending on the measurement conditions), the generator and the capacitor under test. Set the frequency so that the multimeter shows a current that does not exceed 200 μA in the first case, and 2 mA in the second (if the frequency is too low, it will not show anything). Then divide the voltage peak value, expressed in volts, by the square root of two to get the rms value. Convert the current to amperes, and then divide the voltage by the current, and you get the capacitance of the capacitor, expressed in ohms. Then, knowing the frequency and capacitance, calculate the capacitance using the formula:
C = 1 / (2πfR), where C is the capacitance in farads, π is the mathematical constant "pi", f is the frequency in hertz, R is the capacitance in ohms.
Step 4
Convert the capacity calculated in this way into more convenient units: picofarads, nanofarads or microfarads.
