How to judge the quality of the capacitance of a universal meter and the measurement method for the capacitance quality of a universal meter
Because capacitors have charging characteristics, using a resistance range is sufficient. First, adjust the resistance level to the highest level and observe the value. If the capacitor is broken, that is, the capacitor is broken and short circuited, the resistance should display 0 ohms. If it's not bad, it should be from one value to infinity.
There are generally three states of capacitor damage: short circuit, open circuit, and reduced capacity.
It is relatively easy to measure the short circuit and open circuit of capacitors with a multimeter, and the measurement capacity is slightly more complex, and the measurement may not be very accurate.
Measurement: Measured with a pointer multimeter. Set to resistance level. Connect the two probes to either capacitor pin, and then switch the two probes to measure the capacitance pin. Cycle several times. Always check the amplitude of the pointer swing of the multimeter. If it does not slowly return to its original position after swinging, it is a short circuit. If the pointer does not swing at all, it is an open circuit.
If it oscillates and slowly returns to its original position, then this capacitor has no short circuit or open circuit. If you suspect a decrease in capacity, you should compare it with a good capacitor with the same capacity to see if the amplitude of oscillation and return is the same. If it is the same, it is good. It doesn't matter if the swing amplitude is slightly different. If there is too much difference, it means it's broken and should be replaced.
Measure with a digital multimeter: Set to the gear call. The measurement method is the same. If it is a short circuit, the multimeter will keep beeping. If it is an open circuit, the multimeter will not react at all. If it is good, the multimeter will go from calling to not calling. The larger the capacity, the longer the shouting time.
There is electrolyte inside the capacitor, which is easy to dry. Some capacitors with dried electrolyte are placed by the ear and shaken, creating a low, bell like sound inside. Of course, the sound is very low and not as clear as ringing a bell, indicating that it is also bad.、
