Performance requirements for automotive connectors

Performance requirements for automotive connectors

The basic performance requirements for automotive connectors consist of the following three parts:

(1) Electrical performance requirements

The electrical performance of automotive connectors requires them to operate under certain voltage conditions, which varies in different usage environments and safety requirements. The voltage resistance of a connector is related to its own material insulation performance and contact spacing. Therefore, ensuring the reliability and reasonable structure of materials is a requirement for this performance. Due to the presence of the substrate resistance and contact resistance of the connector itself, when a certain current passes through the connector, heat is generated, leading to an increase in the temperature of the connector. When the contact material reaches a certain temperature distance value, its performance will be damaged, leading to connector failure. Therefore, the connector needs to use a flame-retardant insulation material shell and ensure operation under certain rated current conditions. Contact resistance is the most important indicator in the electrical performance of connectors, requiring the contact resistance of the contact point to be below the standard size and ensuring a stable resistance size within a certain range. At the same time, it is required that there should be no thick contaminated film layer. The connector for transmitting signals needs to be sealed with a reasonable casing to shield external signals.

(2) Mechanical performance requirements

Contact pressure is one of the key indicators for measuring the mechanical performance of connectors, which directly affects contact resistance. However, in actual testing and use, due to the connector structure, it is difficult to directly measure the positive pressure of the connector. The contact separation force to some extent reflects the magnitude of the positive pressure. Therefore, relevant standards require that the separation force of connectors (such as GJB1216 and USCAR-20) should be within the specified range. In addition, during the matching process, under the action of friction and positive pressure, the contactor can cause deformation of components such as spring pieces, and larger insertion forces can easily cause stress relaxation and failure of the material. It is required that the insertion force of the connector should not exceed the standard upper limit. Mechanical life is another indicator of connector performance requirements, reflecting the size of connector insertion and extraction times. Once the contactor is inserted or unplugged, adverse effects such as contact surface wear, increased contact resistance, decreased voltage resistance, and matrix deformation and fracture may occur. Therefore, it usually requires connectors to be plugged and unplugged about 500 to 1000 times. Under the action of external vibration and shock loads, the voltage at both ends of the connector can easily decrease for a long time, leading to instantaneous fracture of the connector. This requires the connector to have good vibration and shock resistance performance.

(3) Environmental performance requirements

High temperature environment can affect the performance of automotive connector materials, accelerate the oxidation of metal materials, reduce the elasticity of materials, increase pollution film layers, and deteriorate insulation materials. Wet environments can easily lead to electronic breakdown, material deformation, contact corrosion, metal electrochemical migration, and mold growth. The inhalation of dust particles intensifies the wear of the contact surface and increases the contact resistance. Connectors have high requirements for their complex operating temperature, relative humidity, atmospheric pressure, dust particles, etc.