The principle of action of the connector insulation resistance refers to a resistance value which is applied to the insulating portion of the connector to cause a leakage current to be generated on the surface or inside of the insulating portion. That is, the insulation resistance (MΩ) = voltage (V) / leakage current (μA) applied to the insulator. Through insulation resistance test to determine whether the insulation performance of the connector can meet the requirements of circuit design or to withstand high temperature, humidity and other environmental stresses, whether the insulation resistance meets the relevant technical conditions.

The insulation resistance of the connector is mainly affected by factors such as insulation material, temperature, humidity, fouling, test voltage and duration of continuous application of the test voltage.