How to judge the quality of the capacitance of the multimeter, and the measurement method of the capacitance of the multimeter
Regarding the judgment method of the multimeter capacitor, the multimeter measures the short circuit and open circuit of the capacitor. Generally, there are three states of capacitor damage: short circuit, open circuit, and capacity reduction. This article teaches you how to measure the quality of the capacitor. Let's take a look.
Multimeter to judge whether the capacitor is good or bad
Because the capacitor has charging characteristics, the resistance file can be used. First adjust the resistance gear to the highest level, observe the value, if the capacitor is broken, that is, the capacitor is short-circuited, the resistance should be displayed as 0 ohms. If not bad, it should be from a numeric value to infinity.
Capacitor damage generally has three states: short circuit, open circuit, and capacity reduction.
It is easier for a multimeter to measure the short circuit and open circuit of the capacitor, but it is a little more complicated to measure the reduction of the capacity, and the measurement will not be very accurate.
Measurement: Pointer multimeter measurement. Hit the resistance gear. The two test pens are connected to the two pins of the capacitor at will, and then the two test pens are swapped to measure the two pins of the capacitor. Cycle it a few times. Every time you have to look at the swing range of the pointer of the multimeter, if it does not slowly return to the home position after swinging, it is a short circuit. If the pointer doesn't move at all, it's an open circuit.
If it will swing and return slowly, then the capacitor is not short-circuited or open. If you suspect that the capacity is reduced, compare it with a good capacitor with the same capacity to see if the amplitude of swing and return is the same. It's good to be the same. It doesn't matter if the swing range is a little worse, if it is too much, it is broken and should be replaced.
Measure with a digital multimeter: hit the call file. 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 respond at all. If it is good, the multimeter will go from beating to not beating. The bigger the capacity, the longer the call time.
There is electrolyte in the capacitor, and the electrolyte is easy to dry. Some capacitors with dried electrolytes are shaken by the ear, and there are low-pitched bells in them. Of course, the sound is very low, not as crisp as a bell, which means that it is also bad.
