Method of measuring capacitance using a pointer multimeter
Select the Rx1k or Rx100 range for the pointer multimeter, with the black lead connected to the positive pole of the capacitor and the red lead connected to the negative pole of the capacitor. If the needle quickly swings to the right and then slowly returns to near infinity (∞ Ω), it indicates that the capacitor is normal and has a large capacity; If the return value is less than infinity, it indicates that the leakage current of the capacitor is high, and the pointer reading is the leakage resistance value of the tested capacitor (the leakage resistance of aluminum electrolytic capacitors should exceed 200k Ω before use); If the pointer does not swing to the right at all, it indicates that the capacitor has internal circuit breakers or the electrolyte has dried up and lost capacity; If the pointer swings significantly, approaching 0 Ω, and does not return, it indicates that the capacitor has been broken down.
Which gear is used for measuring capacitance with a multimeter
This requires selecting the corresponding range based on the approximate size of the measured capacitance:
The 000p range is suitable for measuring capacitance below 2000pF;
20n level, suitable for measuring capacitance between 2000pF and 20nF;
200n level, suitable for measuring capacitance between 20nF and 200nF;
two μ Gear, suitable for measuring 200nF to 2 μ The capacitance between F;
twenty μ Gear, suitable for measuring 2 μ F to 20 μ The capacitance between F.
Precautions for using a multimeter to measure capacitance
Before measuring, it is necessary to first cut off the power and discharge the capacitor. The method of discharging is to find a metal object such as a screwdriver, hold the bare part of the metal on the insulation handle and put the two feet of the measured capacitor on it. The capacitance is measured using a digital multimeter, locate the capacitor stop, and then plug the two feet of the capacitor into the capacitance measurement socket after discharging. The actual value is the capacitance of the side capacitor when the reading on the LCD screen stabilizes, If measuring leakage, the resistance range of a pointer type multimeter can be used for measurement. When measuring, a small capacity capacitance multimeter can be placed in RX1K or RX100. When the two probes are connected to the two feet of the capacitor when measuring the display on the dial, the pointer deflects clockwise. Then, as the capacitor is fully charged and there is no current flow, the pointer will counterclockwise and return to infinity. The larger the angle of the pointer, the greater the capacity, During the deflection process, the pointer should swing at a constant speed so that it can return to infinity, indicating that there is no leakage of the capacitor. If the needle suddenly slows down or does not return at a certain position on the dial, it indicates that there is leakage of the capacitor in a certain section. If it finally displays infinity, it indicates that there is no leakage. However, this can only be judged preliminarily. To find an accurate value, it is necessary to observe the characteristics on a capacitance meter, capacitance leakage tester, or oscilloscope, This is something that ordinary people cannot possess. There are also capacitors that have withstand voltage values. The withstand voltage values of electrolytic capacitors are generally written on them, and some ceramic capacitors are not marked on them. Be careful when selecting them.
