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iScience
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Dielectric break down... i understand that there is current passing through the insulator but why is this damaging to the insulator? please go as deep as you can. thankyou
iScience said:@ Davenn , i don't understand. Are you saying that the current surge due to the short will mess up the capacitor plates due to heat?
iScience said:Dielectric break down... i understand that there is current passing through the insulator but why is this damaging to the insulator? please go as deep as you can. thankyou
BertHickman said:Dielectric breakdown is not always damaging. For example, when it occurs in gases and many liquid dielectrics, the dielectric can recover all (or most) of its previous insulating capability once the arc or spark is extinguished. In gases, the conductive plasma channel taken by the discharge cools and dissipates, and the gas recovers its full dielectric strength. In liquids, the gaseous extinguished channel breaks up and if the gaseous byproducts of breakdown can fully dissipate, the liquid will recover most, or all, of its dielectric strength.
However, in a solid, a permanent breakdown channel is created, and the resulting hollow tube/fracturing now contains gases that have a much lower breakdown strength than the solid dielectric. In addition, heat from the electrical discharge may also reduce the dielectric strength of solid dielectric surrounding the channel, such as charring of organic dielectrics. The damaged dielectric can no longer withstand as much voltage, so it more easily breaks down along the damaged path and never regains its original dielectric strength.
Dielectric breakdown is damaging because it causes a breakdown in the insulating properties of a material, leading to a flow of electric current. This can result in electrical short circuits, fires, and damage to electronic components.
Dielectric breakdown occurs when the electric field strength applied to a material exceeds its dielectric strength. This can be caused by high voltages, physical stress, or exposure to moisture or contaminants.
The effects of dielectric breakdown can range from minor disruptions to catastrophic damage. In electronic devices, it can cause malfunctions or complete failure. In power systems, it can lead to electrical fires and blackouts. In industrial settings, it can damage equipment and halt production.
Dielectric breakdown can be prevented by using materials with high dielectric strength, ensuring proper insulation and spacing in electronic devices, and regularly testing and maintaining electrical equipment. It is also important to follow safety protocols and avoid exposing materials to extreme conditions.
Some examples of materials with high dielectric strength include glass, ceramic, rubber, and certain plastics such as polyethylene and polypropylene. These materials are often used as insulators in electronic devices and power systems to prevent dielectric breakdown.