The so-called deterioration refers to the phenomenon that insulation performance degrades under the effects of electric field, heat, chemistry, mechanical force, atmospheric conditions, and other factors. The intelligent test bench for switch plug protection performance is used for various models and manufacturers of high-voltage distribution device relay protection plugs, vacuum feeder protection plugs, vacuum electromagnetic starter protectors, electric drill comprehensive protection plugs, and lighting signal comprehensive protection plugs, whose performance deteriorates. Some deteriorated insulation is reversible, while some is irreversible. For example, when insulation is damp, its performance decreases, but after drying, it recovers its original insulation performance; obviously, it is reversible. Another example is that some engineering plastics show reversible fluctuations in mechanical properties under different humidity and temperature conditions. Such reversible changes are essentially physical changes, not involving changes in chemical structure, and do not belong to aging. Aging, on the other hand, is a series of chemical and physical changes that occur in insulation under long-term effects of various factors, leading to continuous decline in electrical and mechanical properties. There are many causes of insulation aging, but common aging in electrical equipment insulation is electrical aging and thermal aging. For example, partial discharge produces ozone, which easily causes ozone cracking in insulating materials, leading to material performance aging. Under the high temperature of an arc, oil can decompose carbon particles, and oil is oxidized to generate water and acids, all of which gradually age the oil. From the above analysis, it can be seen that deterioration has a broader meaning, while aging has a relatively narrower meaning; aging is only one aspect of deterioration.
