Automobile harness terminal is a kind of conductive element that can form a circuit with corresponding conductive elements. The connector includes plug and Jack, which plays the role of electrical connection. The materials used are conductors of copper and its alloy, whose surfaces shall be silver, gold or tin plated to improve corrosion resistance, anti-oxidation and rust protection.

1) Terminal type

According to its shape, the terminals can be divided into sheet series, cylindrical series and linear connection series . 

The wiring material for sheet series is H65Y or H70Y, and its material thickness is 0.3 ~ 0.5. Figure 2 shows a schematic diagram of the components.

2) The wiring material for the cylinder series is H65Y or Qsn6.5-0.1 with material thickness 0.3 ~ 0.4. Schematic diagram of the components is shown in Figure 3.

3) The terminal blocks connected by wires are divided into three types: U-type, fork-type and hole-type.

① U-type junction box made of H62Y2, H65Y, H68Y or Qsn6.5-0.1, the material thickness is 0.4~0.6;

② Fork terminal is also known as Y-type terminal. The material of Y-type terminal is H62Y2, with material thickness of 0.4 ~ 0.6, local nickel plating and good conductivity. See Fig. 4b for schematic diagram of some components;

③ H65Y and H65Y2 are generally used as the base materials, the thickness of hole terminal is 0.5 ~ 1.0. The schematic diagram of some components is shown in Fig. 4c.

Principles of selecting automobile harness terminals

Different wiring modes can be selected according to different connectors and needs. Equipment with high performance requirements, such as airbag junction box, ABS and ECU, gold-plated parts shall be preferred to ensure safety and reliability; considering the cost, local gold plating can be selected to meet the performance requirements.

The specific principles of selection are as follows:

① Make sure that the terminal matches the selected plug.

② Select the appropriate posts according to the diameter of the pressed wire.

③ After the single-hole waterproof plug-in is selected, terminal available for pressing water shall be selected.

④ Ensure reliable connection. When selecting wiring posts, ensure good contact with electrical components, minimize contact resistance and improve reliability. For example, surface contact is better than point contact, and pinhole type is better than plate spring type. The connector for double spring pressure device (with small contact resistance) shall be preferred for design. 

⑤ Impedance matching: Impedance matching requirements for certain signals, especially RF signals, are much stricter. Impedance mismatch will lead to signal reflection and affect signal transmission. Therefore, when selecting an automobile harness terminal, be sure to choose the impedance matching.