1. Poor contact
The metal conductor inside the terminal is the core part of the terminal. It transmits the voltage, current or signal from the external wire or cable to the corresponding contact of the corresponding connector. Therefore, the contact must have an excellent structure, stable and reliable contact retention and good electrical conductivity. Due to the unreasonable structural design of the contact, incorrect selection of materials, unstable mold, poor processing dimensions, rough surface, heat treatment and electroplating, and other surface treatment processes are unreasonable, improper assembly, poor storage and use environment and improper operation and use will cause Contact and mating 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 from the contacts and between the contacts and the housing. Therefore, the insulation parts must have excellent electrical properties, mechanical properties and process forming properties. Especially with the widespread use of high-density, miniaturized terminal blocks, the effective wall thickness of insulators is getting thinner and thinner. This imposes more stringent requirements on insulation materials, injection mold accuracy and molding processes. Due to the presence or absence of excess metal on the surface of the insulator, surface dust, flux and other contamination and moisture, organic material precipitates and harmful gas adsorption films fuse with the surface water film to form ionic conductive channels, moisture absorption, mold growth, aging of insulation materials, etc. Will cause short circuit, leakage, breakdown, low insulation resistance and other poor insulation phenomena.
3. Poor fixation
Insulators not only play an insulating role, but also generally provide centering and protection for protruding contacts. At the same time, they also have the functions of installation and positioning, and locking and fixing on the equipment. Poor fixation, light affects the reliability of the contact and causes instant power failure, the most serious is the product disintegration. Disassembly refers to the abnormal separation between the plug and the socket, and the abnormal separation between the pin and the socket caused by the unreliable structure of the terminal in the mated state due to materials, design, and technology. Serious consequences of signal control interruptions. Due to unreliable design, wrong material selection, improper selection of molding process, poor quality of heat treatment, mold, assembly, welding, etc., and poor assembly will cause poor fixing.
In addition, the appearance is not good due to peeling, corrosion, bruising, flashing of the plastic shell, cracking, rough processing of contacts, deformation, etc., due to the poor positioning and locking fit, poor processing quality consistency, and excessive total separation force. Poor interchange caused by other reasons is also a common disease and frequently-occurring. These kinds of faults can generally be found and eliminated in time during inspection and use.