What can cause the multimeter not to respond when measuring capacitance?
If it's a digital multimeter not responding to the capacitor. Firstly, make sure the gear and jack are correct, and secondly that the multimeter is not broken. This kind of low-level error is usually not out of line. If the multimeter is normal and the gear is correct, it is most likely that the capacitor is bad. When the capacitor is damaged internally by an open circuit (burned out), the multimeter shows zero.
Another possibility is that when measuring capacitance with a multimeter, you must first discharge the electricity inside the capacitor, otherwise the internal components of the multimeter may be damaged. For small-capacity capacitors, directly short the two pins of the capacitor can be. For large-capacity capacitors or cable discharge can not be directly shorted, otherwise the huge heat generated by shorting will lead to capacitance bulging or even explosion. The correct approach is to connect a resistor or electrical equipment to both ends of the capacitor, so that the resistor or electrical equipment to consume the power.
(When selecting an electrical device, it is important to ensure that the rated voltage of the electrical device is higher than the capacitor's voltage.)
Pointer multimeter
1. If you are using a pointer multimeter, it is possible that the capacitance stop is selected too large. The capacitance and resistance of the pointer multimeter are one and the same, the larger the resistance, the smaller the capacitance.
Resistance × 100K gear is capacitance C × 0.1 gear; resistance × 1 gear is capacitance C × 10K gear. 2.
2. There is also a situation where the capacitor is damaged. When the capacitor internal open circuit (disconnected), the multimeter pointer will not have any response. When the capacitor internal short-circuit (shorted), the multimeter pointer will always stop again resistance zero scale there.
Under normal circumstances with the pointer multimeter capacitance measurement, the pointer will be quickly deflected to the right, and then slowly go back, and finally stop at a certain position. The larger the capacitance, the larger the angle of the pointer to the right; the better the quality of the capacitance, the pointer finally stops closer to infinity. 3.
3. There is also a capacitor is not discharged. Measurement of capacitance with a pointer multimeter, every time you need to re-measure the need to re-discharge (shorted). Some friends say I did not discharge the first time? Because every time you measure the capacitance with the capacitance mode (actually resistance mode), the internal battery of the multimeter will charge the capacitance. So every time you need to re-measure after measurement, you have to short the capacitor.
