The plastic insulating material and conductive parts of the terminal are directly related to the quality of the terminal, and they respectively determine the insulating and conductive properties of the terminal. The failure of any one terminal will lead to the failure of the entire system engineering. 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.
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 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, the 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 environments, and improper operation and use, all contact parts will be damaged. The contact part and the matching part cause poor contact.
2. Poor insulation
The function 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
Performance, mechanical properties and process molding properties. Especially with the widespread use of high-density and miniaturized terminals, the effective wall thickness of the insulator becomes thinner and thinner. This puts more stringent requirements on insulating materials, injection mold accuracy and molding technology. 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, aging of insulation materials, etc. Will cause short-circuit, leakage, breakdown, low insulation and other poor insulation.
3. Poor fixation
The insulator not only provides insulation, but also provides accurate centering and protection for the protruding contacts. It also has the functions of installation and positioning, and locking and fixing on the equipment. Poor fixation, the lighter will affect the reliable contact and cause instantaneous power failure, the more serious is the product disintegration. Disassembly refers to the abnormal separation between the plug and the socket, the pin and the socket caused by the unreliable structure of the terminal in the plug-in state due to material, design, process and other reasons, which will cause the power transmission of the control system. Serious consequences of signal control interruption. Due to unreliable design, wrong material selection, improper selection of molding process, poor quality of heat treatment, mold, assembly, welding and other processes, and improper assembly will cause poor fixing.
In addition, due to coating peeling, corrosion, bruising, plastic shell flashing, cracking, rough processing of contact parts, deformation, etc., the appearance is poor, due to the out-of-poor positioning and locking fit size, poor processing quality uniformity, and total separation force Poor interchange caused by major causes is also a common disease and frequently-occurring disease. These types of faults can generally be found and eliminated in time during inspection and use.
Reliability screening test to prevent failure
In order to ensure the quality and reliability of the terminal blocks and prevent the occurrence of the above-mentioned fatal failures, it is recommended to study and formulate the corresponding screening technical requirements according to the technical conditions of the product, and carry out the following targeted failure prevention reliability tests.
fuse terminal block
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.
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 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, the 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 environments, and improper operation and use, all contact parts will be damaged. The contact part and the matching part cause poor contact.
2. Poor insulation
The function 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
Performance, mechanical properties and process molding properties. Especially with the widespread use of high-density and miniaturized terminals, the effective wall thickness of the insulator becomes thinner and thinner. This puts more stringent requirements on insulating materials, injection mold accuracy and molding technology. 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, aging of insulation materials, etc. Will cause short-circuit, leakage, breakdown, low insulation and other poor insulation.
3. Poor fixation
The insulator not only provides insulation, but also provides accurate centering and protection for the protruding contacts. It also has the functions of installation and positioning, and locking and fixing on the equipment. Poor fixation, the lighter will affect the reliable contact and cause instantaneous power failure, the more serious is the product disintegration. Disassembly refers to the abnormal separation between the plug and the socket, the pin and the socket caused by the unreliable structure of the terminal in the plug-in state due to material, design, process and other reasons, which will cause the power transmission of the control system. Serious consequences of signal control interruption. Due to unreliable design, wrong material selection, improper selection of molding process, poor quality of heat treatment, mold, assembly, welding and other processes, and improper assembly will cause poor fixing.
In addition, due to coating peeling, corrosion, bruising, plastic shell flashing, cracking, rough processing of contact parts, deformation, etc., the appearance is poor, due to the out-of-poor positioning and locking fit size, poor processing quality uniformity, and total separation force Poor interchange caused by major causes is also a common disease and frequently-occurring disease. These types of faults can generally be found and eliminated in time during inspection and use.
Reliability screening test to prevent failure
In order to ensure the quality and reliability of the terminal blocks and prevent the occurrence of the above-mentioned fatal failures, it is recommended to study and formulate the corresponding screening technical requirements according to the technical conditions of the product, and carry out the following targeted failure prevention reliability tests.
fuse terminal block