Introduction to Precautions for Measuring Capacitance with a Multimeter
Before measurement, it is necessary to cut off the power and discharge. The method of discharging is to find a metal object such as a screwdriver, hold it on the exposed part of the metal on the insulating handle, and place the two legs of the measured capacitor on the two legs. The capacitance measurement is measured with a digital multimeter, find the correct capacitance range, and then discharge the capacitor. The two legs are inserted into the capacitance measurement socket or other LCD screen. The stable reading is the capacitance of the measured capacitor. If leakage is detected, the resistance range of the pointer type multimeter can be used for measurement. When measuring, the small capacity capacitance multimeter can be placed in RX1K or RX100 When measuring the display on the dial, when the two probes are connected to the two legs of the capacitor, the pointer deflects clockwise. Then, as the capacitor is fully charged inside, due to the absence of current flow, the pointer will discharge counterclockwise and return to infinity. The larger the angle of the pointer, the larger the capacity. During the deflection process, the pointer needs to swing at a constant speed so that it can return to infinity, indicating that the capacitor is not leaking electricity. If the pointer suddenly slows down or does not return at a certain position on the dial, it indicates that the capacitor is leaking electricity in a certain section. If it finally displays as infinity, it indicates that there is no leakage electricity. However, this can only be roughly judged. To find the accurate value, it is necessary to observe the characteristics with a capacitance meter, capacitance leakage tester or oscilloscope. This is not possible for ordinary people. possessed. Capacitors also have a withstand voltage value, and the withstand voltage value of electrolytic capacitors is usually written on it. When selecting ceramic capacitors, it is important to note that some are not labeled on it.
