How to measure how charged a capacitor is
voltmeter. measure the DC voltage across it. Just remember that measuring the tension will start to decrease it. capacitor is just like bucket. put water (that is, water) to fill the bucket.
If you know the charging voltage, simply measure the voltage on the capacitor to see how much it is charging. assume that if the charging voltage is 12 VDC and the voltage across the capacitor is 6 VDC. then the capacitor is 50% charged.
A multimeter determines the capacitance by charging a capacitor with a known current, measuring the resulting voltage, and then calculating the capacitance. use your digital multimeter (dmm) to make sure the circuit is turned off. If the capacitor is used in an AC circuit, set up the multimeter to measure the AC voltage. If used in a continuous circuit, set the dmm to measure DC voltage.
Visually inspect the capacitor. If leaks, cracks, bulges, or other signs of deterioration are evident, replace the capacitor.
Turn the dial to the capacity measurement mode (). the symbol often shares a place on the dial with another function. in addition to setting the dial, it is usually necessary to press a function button to activate a measurement. consult the user’s manual of your multimeter for instructions.
Some multimeters offer a relative mode (rel). When measuring low capacitance values, the relative mode can be used to suppress the capacity of the test leads. to place a multimeter in relative mode for capacity, leave the test leads open and press the rel button. this removes the residual capacity value of the test leads.
connect the test leads to the capacitor terminals. Leave the test leads connected for a few seconds to allow the meter to automatically select the appropriate range.
Reads the displayed measure. If the value of the capacitance is within the measuring range, the multimeter displays the capacitor value. it will show ol if a) the value of the capacitance is greater than the measuring range or b) the capacitor is defective.