The harness terminals such as quality, will seriously affect the devices and related links Unicom problem. The plastic insulating material and the conductive member is directly related to the quality of the terminal, which respectively determine the insulating properties and electrical conductivity of the terminals. The terminals failure will result in the failure of the whole system works. The painful lesson home and abroad in this regard is very profound.
Terminal block from the use of perspective, the function should be achieved: contact with parts of the conduction must be turned on to make solid contact. The place must be insulated parts should not be conducting the wire insulation should not be exposed. According to the Ho Chi electronic wiring harness production sector, the common terminals fatal failure in the form of the following three:

First insulating sheath poor quality

   
The role of the insulator is to maintain the correct positions are arranged so that the contact member and the contact member and the contact member between the mutual insulation between the contact member and the casing. Therefore, the insulating member must have excellent electrical properties, mechanical properties and molding process performance. Especially with the widespread use of high density, small terminals, the effective wall thickness of the insulator are increasingly thin. This proposed more stringent requirements for insulation materials, plastic injection mold precision molding process. Insulator surface or internal moisture contamination of the metal extra material, surface dust, flux, organic material precipitates and harmful gas adsorption membrane fusion with the surface of the water film to form ionic conductive channel to absorb moisture, mildew, aging of insulation materials, will cause a short circuit, leakage, breakdown, low insulation resistance of insulation undesirable phenomena.

Second. Poor contact

The terminals of internal metal conductor is the core parts of the terminal, it to the wire or cable from an external voltage, current, or a signal transmitted to the corresponding contact member and its mating connector. So the contacts must have excellent structure, to maintain a stable and reliable contact force and good electrical properties. Of contacts unreasonable structural design, material selection, error, mold unstable processing size ultra-poor, rough surface, heat treatment electroplating and surface treatment processes such as unreasonable, improper assembly, storage harsh environments and operating improper use will be in contact with pieces The site of contact with the site cause poor contact.

Terminal block fixed bad

   
The insulator not only from the insulation, usually projecting contact member to provide accurate and protection, while also having a mounting positioning, the locking function is fixed on the device. Fixed bad, the light affect contact reliable cause a momentary power failure, serious is the product of the disintegration. Disintegration is the terminal mating state, due to the materials, design, technology, and other causes unreliable structure caused between the plug and socket between the pin and the jack is not normal separation will result in the control system for power transmission and Signal control interrupt serious consequences. Unreliable because of the design, material selection error, improper selection of the molding process, heat treatment, mold, assembly, welding, poor workmanship, assembly is not in place will result in fixed bad.

   
In addition, due to the coating corrosion, bumps, broken, and rough contact parts processing, deformation, and other causes of bad appearance, is also common and frequently-occurring. These failures must be found in the inspection and the use of the process in a timely manner is removed in order to maintain better connectivity performance.