The plastic insulating material and conductive parts of the terminal are directly related to the quality of the terminal, and they respectively determine the insulation and conductivity of the terminal. The failure of any one terminal will lead to the failure of the entire system project. The painful lessons at home and abroad in this regard are very profound.

Prevention is the goal, and analysis is the foundation. In a sense, preventing failure is more important than analyzing failure. It has a more realistic meaning for ensuring the quality and reliability of the terminal.

From the point of view of use, the function of the terminal block should be: the conductive part of the contact part must be conductive and the contact is reliable. Places where the insulation should not be conducted must be insulated reliably. There are three common fatal failure forms of terminal blocks:

1. Poor contact

The metal conductor inside the terminal is the core part of the terminal, which transmits the voltage, current or signal from the external wire or cable to the corresponding contact of the connector. Therefore, the contact must have an excellent structure, stable and reliable contact retention and good electrical conductivity. Due to the unreasonable structure design of the contact parts, wrong material selection, unstable molds, out-of-poor processing dimensions, rough surface, unreasonable surface treatment processes such as heat treatment and electroplating, improper assembly, harsh storage and use environment, and improper operation and use, all contact parts Contact parts and matching parts cause poor contact.

2. Poor insulation

The role of the insulator is to keep the contacts in the correct position and to insulate the contacts and the contacts, and between the contacts and the housing. Therefore, the insulating parts must have excellent electrical properties, mechanical properties and process molding properties. Especially with the widespread use of high-density and miniaturized terminals, the wall thickness of the insulator is getting thinner and thinner. This puts more stringent requirements on insulating materials, injection mold accuracy and molding process. Due to the existence of metal excess on the surface or inside of the insulator, surface dust, flux and other pollution and moisture, organic material precipitates and harmful gas adsorption film merge with the surface water film to form ionic conductive channels, moisture absorption, mold growth, and aging of insulating materials. Will cause short circuit, leakage, breakdown, low insulation resistance and other poor insulation.