Measurement of large capacitances with a multimeter
If the capacitance is relatively large, generally adjust the resistance range of the multimeter to ×10 or ×100, and use two test leads to touch both ends of the large capacitor. The needle of the meter will fluctuate greatly, and then gradually return to zero. Then adjust the meter pens, and the needle of the meter will There are very large fluctuations, and the meter needle may even move. The greater the fluctuation, the greater the capacitor capacity, which proves that the capacitor is not broken. If the meter needle does not fluctuate, or the fluctuation is very small, it proves that the capacitor has reduced its capacity and cannot be used. .
Note: When measuring capacitance with a multimeter, try to start with a small setting and gradually use a large setting to avoid damaging the meter needle.
In addition, there is an error in the measurement of high-voltage capacitors, and the measurement may be inaccurate, because high-voltage capacitors have no problem at low voltage, but problems will occur at high voltage. The voltage of the multimeter is only 1.5 volts, so the high-voltage capacitor Sometimes measurements using a multimeter are inaccurate.
The above can only determine whether the capacitor is good or bad, but cannot determine the specific capacity of the capacitor.
Select the range corresponding to the resistance value and then start measuring.
The resistor value you mentioned is very large. I wonder how big it is? For example, if the value exceeds the value of the multimeter, you can try to measure the voltage and current values to calculate the resistance value.
Large capacitors can be tested for electrical resistance with a multimeter. This only roughly detects failure, short circuit, and how much the capacitor has dropped. A special capacitance tester must be used to detect it. For PF capacity level capacitors, a multimeter cannot roughly detect whether it is good or bad!
To measure super large capacitance, use a pointer multimeter to measure and first set the electrical barrier Rⅹ1. Look at the deflection time of the pointer. The larger the capacity, the longer the time will take to indicate the size of its capacitance. If there is no above reaction, it means there is no capacity.
