Safety capacitance detection and substitution (II)

2, the safety capacity of the capacitor test

The capacitance of the safety capacitor is usually measured by a digital multimeter or digital capacitance tester. If there is no digital multimeter and digital capacitance tester, an analog multimeter can be used for simple estimation. For a capacitor with a capacitance of 1 μF or more, the following method can be used: Use a multimeter R×1K block to detect. When using a multimeter, the two table pens touch the two pins of the capacitor, observe the deflection angle of the pointer, and then with several good ones. Knowing the capacity of the safety capacitors can be roughly estimated. Note that it is normal for the commonly used capacitance to have an error of 20% of the nominal capacity. For a capacitor with a capacity of 1 μF or less, the instrument must be able to measure the capacity accurately.

3, replacement of safety capacitor capacitance

In case of breakdown (short-circuit), burn-out (open-circuit), leakage, and failure, the safety capacitor is generally replaced with a capacitor of the same type and specification. If the same type is not available, substitutes can be used. The principle is: the capacity is basically the same, and the pressure resistance is greater than or equal to the pressure resistance of the original capacitor. Of course, the volume of the substitute should be similar to that of the original capacitor, otherwise it may not be installed. If no suitable safety capacitor can be found, other types of safety capacitors can also be used to obtain suitable capacitors through series or parallel connection.