Use the resistance gear, select the appropriate range according to the capacitance capacity, and pay attention to the positive electrode of the capacitor for the black test lead of the electrolytic capacitor during measurement.
①. Estimate the size of the microwave-class capacitor capacity: it can be determined by experience or by referring to the standard capacitor of the same capacity, according to the maximum amplitude of the pointer swing. The reference capacitors do not have to have the same withstand voltage value, as long as the capacity is the same. For example, estimating a 100μF/250V capacitor can be referenced by a 100μF/25V capacitor. As long as the maximum amplitude of their pointer swings is the same, it can be concluded that the capacity is the same.
②. Estimate the capacitance of the picofarad-level capacitor: use the R×10kΩ file, but only the capacitance above 1000pF can be measured. For 1000pF or slightly larger capacitors, as long as the needle swings slightly, it can be considered that the capacity is sufficient.
3. Measure whether the capacitor is leaking: For capacitors above 1,000 microfarads, you can use the R×10Ω gear to quickly charge it first, and initially estimate the capacitance, then change to the R×1kΩ gear and continue to measure for a while. Should return, but should stop at or very close to ∞, otherwise there will be leakage. For some timing or oscillating capacitors below tens of microfarads (such as the oscillating capacitors of color TV switching power supplies), their leakage characteristics are very high, and they cannot be used as long as there is a slight leakage. Then use the R×10kΩ gear to continue the measurement, and the needle should stop at ∞ instead of returning.
