The main functions of insulators are to achieve electrical insulation and mechanical fixation, and various electrical and mechanical performance requirements are stipulated for this purpose. For example, under the specified operating voltage, lightning overvoltage and internal overvoltage, no breakdown or surface flashover occurs; under the specified long-term and short-term mechanical loads, no destruction or damage occurs;

The main functions of insulators are to achieve electrical insulation and mechanical fixation, for which various electrical and mechanical performance requirements are specified.

For example, under the specified operating voltage, lightning overvoltage and internal overvoltage, no breakdown or surface flashover occurs; under the specified long-term and short-term mechanical load, no destruction or damage occurs; after long-term operation under the specified mechanical and electrical loads and various environmental conditions, no obvious degradation occurs; the hardware of the insulator does not produce obvious corona discharge under the operating voltage to avoid interfering with radio or television reception. Because insulators are widely used devices, their connecting hardware is also required to be interchangeable.

In addition, the technical standards for insulators also require that insulators be subjected to various electrical, mechanical, physical and environmental condition tests depending on the model and conditions of use to verify their performance and quality.