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Another equivalent version is a single charged capacitor short circuited by a perfect conductor. In these cases in the final state the entire charge has been neutralized, the final voltage on the capacitors is zero, so the entire initial energy has vanished. The solutions to where the energy went are similar to those described in the previous ...
Failed aluminium electrolytic capacitors with open vents in the top of the can, and visible dried electrolyte residue (reddish-brown color) The capacitor plague was a problem related to a higher-than-expected failure rate of non-solid aluminium electrolytic capacitors between 1999 and 2007, especially those from some Taiwanese manufacturers, [1] [2] due to faulty electrolyte composition that ...
Structurally, capacitors consist of electrodes separated by a dielectric, connecting leads, and housing; deterioration of any of these may cause parameter shifts or failure. Shorted failures and leakage due to increase of parallel parasitic resistance are the most common failure modes of capacitors, followed by open failures.
At low frequencies parasitic capacitance can usually be ignored, but in high frequency circuits it can be a major problem. In amplifier circuits with extended frequency response, parasitic capacitance between the output and the input can act as a feedback path, causing the circuit to oscillate at high frequency.
The electrolytic capacitors used in equipment of 1960s vintage contained liquid electrolyte, which dried out over decades, decreasing the capacitance and increasing the leakage current, and these are often the cause. One solution suggested is a "capacitor job", replacing all the old electrolytic capacitors.
Leakage is equivalent to a resistor in parallel with the capacitor. Constant exposure to factors such as heat, mechanical stress, or humidity can cause the dielectric to deteriorate resulting in excessive leakage, a problem often seen in older vacuum tube circuits, particularly where oiled paper and foil capacitors were used.
The frequency dependence of inductance values gives rise to other constraints on this type of bridge: the calibration frequency must be well below the lesser of the self-resonance frequency of the inductor and the self-resonance frequency of the capacitor, Fr < min(L srf,C srf)/10. Before those limits are approached, the ESR of the capacitor ...
passive sources of reactive power (e. g., shunt or series capacitors). shunt capacitors are used in power systems since the 1910s and are popular due to low cost and relative ease of deployment. The amount of reactive power supplied by a shunt capacitor is proportional to the square of the line voltage, so the capacitor contributes less under ...