1.What is Capacitor？
Capacitors are components that store electric quantity and energy (electric potential energy). One conductor is surrounded by another conductor, or the electric field lines emitted by one conductor all terminate in the conductor system of the other conductor, which is called a capacitor.
2.Common faults of capacitors？
Common faults of capacitors include disconnection, short circuit, leakage and failure.
(1) Determination of capacitor: set multimeter to block r×1k or r×10k, and contact the two probes with the two poles of the capacitor respectively. If the pointer of the meter rapidly swings forward by an angle, then gradually recovers and returns to the starting position. Then exchange the two pens, contact the two poles of the capacitor, the pointer of the meter deflects forward again, and the rotation angle is larger than that of the previous one, then gradually recovers and returns to the starting position, indicating that the capacitor is in good condition. The larger the deflection angle of the pointer, the slower the recovery speed, indicating the larger the capacitor.
(2) Leakage: Multimeter (r×1k gear). When stable, the indicator value of the pointer is the insulation resistance of the capacitor. A certain value is usually several hundred to several gigaohms. The larger the resistance value, the better the insulation performance of the capacitor.
(3) short circuit: if the multimeter pointer swings to full scale, i.e. r=0, but does not return, it indicates that the capacitor is short-circuited.
(4) disconnection: when the two probes of the multimeter contact the capacitor electrode, the pointer does not deflect at all, and the exchanged probes still do not deflect, indicating that the capacitor has been disconnected.
(1) The capacitor removed from the circuit shall be subjected to short-circuit discharge to prevent the residual charge on the polar plate from damaging the instrument or affecting personal safety during discharge.
(2) Do not touch the conductor part of the stylus with both hands during the test, so as not to affect the measurement results due to human resistance intervention.