Analysis of Common Failures of Wiring Terminals

The plastic insulating material and conductive parts of the Terminal Block Connector 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 engineering. It is said that prevention is the goal and analysis is the foundation. Point out that from a certain use angle, the function that the terminal should achieve is: the conductive part of the contact part must be conductive, and the contact is reliable. Places where the insulating parts should not be conductive must be insulated reliably.

There are three common failure modes of terminal blocks:

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, the unstable mold, the out-of-poor processing size, the rough surface, the unreasonable surface treatment processes such as heat treatment and electroplating, improper assembly, poor storage and use environment, and improper operation and use, all contact parts Contact parts and matching parts cause poor contact.

Terminal Block Connector

2. Poor insulation

The function of the insulator is to keep the contact pieces aligned in the correct position, and to insulate the contact piece and the contact piece, and between the contact piece 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 Industrial Terminal, 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 an ionic conductive channel, moisture absorption, mold growth, insulation material aging and other reasons, Will cause short circuit, leakage, breakdown, low insulation resistance 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 plugged 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 fixation.

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 consistency, 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.

Without reliable wiring terminals, there is no reliable system engineering. Failure and reliability are two aspects of a contradictory body that are corresponding and interrelated. Finding various failure modes and failure mechanisms through the reliability screening of Brass Terminal Block can draw a lot of experience and lessons and eliminate various hidden dangers, and provide scientific basis for improving design, process, inspection and use. It is also the revision and formulation of technical conditions for terminal blocks Important basis for Finding measures to prevent failures and realizing the transformation from failure to reliability is the ultimate goal of failure analysis.