The harness terminal is a conductive element that can form a circuit with the corresponding conductive element. The terminal includes two kinds of pins and sockets, which play the role of electrical connection. The materials used are good conductors such as copper and its alloys. The surface is plated with silver, gold or tin to improve corrosion resistance and oxidation resistance. and anti-rust.
1. Terminal type
Terminals can be divided into sheet series, cylindrical series and wire joint series according to their shape.
1) The chip series terminals are made of H65Y or H70Y material, and the material thickness is 0.3 to 0.5.
2) The cylindrical series terminals are made of H65Y or Qsn6.5-0.1 material, and the material thickness is 0.3 to 0.4.
3) Wire connector series terminals are divided into three types: U-shaped, fork-shaped and hole-shaped.
① The U-shaped terminal is made of H62Y2, H65Y, H68Y or Qsn6.5-0.1 material, with a thickness of 0.4 to 0.6;
②The fork terminal is also called the Y-type terminal. The Y-type terminal is made of H62Y2 material, with a material thickness of 0.4 to 0.6, and part of the surface is nickel-plated, with good electrical conductivity;
③ Hole terminals generally use H65Y and H65Y2 as the base material, and the material thickness is 0.5 to 1.0.
2. Terminal selection principle
Different plated terminals should be selected according to different connectors and different needs. For equipment with high performance requirements, such as terminals for airbags, ABS, ECU, etc., gold-plated parts should be preferred to ensure safety and reliability, but due to cost considerations, partial gold-plated treatment can be selected under the premise of meeting performance requirements.
The specific selection principles are:
① Ensure that the terminals are reasonably matched with the selected connectors.
②Select the appropriate terminal for the wire diameter of the crimped wire.
③For the single-hole waterproof connector, select the terminal whose tail can be crimped to the waterproof plug.
④ Ensure the reliability of the connection. When selecting terminals, ensure good contact with electrical devices and plug-ins, so as to minimize contact resistance and improve reliability. For example, surface contact is better than point contact, and pinhole type is better than leaf spring type. In the design, it is preferable to use a connector with a double spring compression structure (very low contact resistance).
⑤ Impedance matching. Some signals have impedance matching requirements, especially RF signals, which have stricter impedance matching requirements. When the impedance is not matched, signal reflection will be caused, thereby affecting signal transmission. Therefore, when selecting a terminal, be sure to select a terminal with matching impedance.