Capacitance Meters

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Capacitance Meters
Capacitance Meters

Capacitance Meter is a piece of electronic test equipment used to measure capacitance, mainly of discrete capacitors. Depending on the sophistication of the meter, it may display the capacitance only, or it may also measure a number of other parameters such as leakage, equivalent series resistance (ESR), and inductance. For most purposes and in most cases the capacitor must be disconnected from circuit; ESR can usually be measured in circuit.

Simple checks without a true capacitance meter

Some checks can be made without a specialised instrument, particularly on aluminium electrolytic capacitors which tend to be of high capacitance and to be subject to poor leakage. Amultimeter in a resistance range can detect a short-circuited capacitor or one with very high leakage . A crude idea of the capacitance can be derived with an analog multimeter in a high resistance range by observing the needle when first connected; current will flow to charge the capacitor and the needle will kick from infinite indicated resistance to a relatively low value, and then drift up to infinity. The amplitude of the kick is an indication of capacitance. Interpreting results requires some experience, or comparison with a good capacitor, and depends upon the particular meter and range used.