In order to ensure the quality and reliability of the terminal and prevent the occurrence of the above-mentioned faults, 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 reliability inspection for failure prevention.

1. Prevention of poor contact

1) Conduction detection

Generally, there is no such item in the product acceptance test of the terminal manufacturer, and the user generally needs to conduct a conduction test after installation. Therefore, it is recommended that manufacturers should increase the point-by-point conduction detection by 100 for some key models.

2) Transient break detection

Some terminals are used in dynamic vibration environment. Experiments show that only testing the static contact resistance is qualified, and can not guarantee the use of dynamic environment contact reliable. Because, often the contact resistance of qualified connectors in vibration, impact and other simulated environmental tests still appear instantaneous power failure phenomenon, so for some high reliability requirements of the terminal, it is best to 100 of its dynamic vibration test to assess its contact reliability.

3) Single hole separation force detection

Single-hole separation force refers to the separation force that the contact in the inserted state changes from static to moving, which is used to indicate that the pin and the socket are in contact. Experiments show that the separation force of single hole is too small, which may cause signal transient break when subjected to vibration and impact load. It is more effective to check the contact reliability by measuring the separation force of a single hole than to measure the contact resistance. Check and find that the single-hole separation force is out of tolerance of the jack, and the measured contact resistance is often still qualified. For this reason, in addition to developing a new generation of stable and reliable flexible plug-in contacts, the manufacturer should not use automatic plug-in force testing machine for key models for multi-point simultaneous testing, and should carry out 100 point-by-point single-hole separation force inspection for finished products to prevent instantaneous signal interruption caused by relaxation of individual jacks.

2. Prevention of poor insulation

1) Insulation material inspection

The quality of raw materials has a great influence on the insulation performance of insulators. Therefore, the choice of raw material manufacturers is particularly important, not blindly reduce costs and lose the quality of materials. Should choose a good reputation of large factory materials. And for each batch of materials to carefully check the batch number, material certificate and other important information. Do a good job of traceability information on the use of materials.

2) Inspection for insulation resistance of insulator

By 2012, some production plants had stipulated that the electrical performance should be tested after assembling the finished products. As a result, the whole batch of finished products had to be scrapped due to the unqualified insulation resistance of the insulator itself. Reasonable process should be 100% process screening in the state of insulator parts to ensure qualified electrical performance.

3. Prevention of poor fixation

1) Interchangeability check

The interchangeability check is a dynamic check. It requires that the same series of matching plugs and sockets can be plugged and connected to each other, and it is found whether there is any reason why the plugs cannot be plugged, positioned and locked due to excessive size of insulators, contacts and other parts, missing parts or assembly is not in place, or even disassembled under the action of rotating force. Another function of the interchangeability check is to find out whether there are metal superfluous objects that affect the insulation performance through the plug connection such as thread and bayonet. Therefore, 100% of the terminals for some important purposes should be inspected to avoid such major fatal failures.

2) Torque resistance inspection

Torque resistance inspection is a very effective inspection method to check the reliability of terminal structure. Such as the United States military standard MIL-L-39012 standards. According to the standard, each batch of samples should be sampled for torque resistance inspection to find problems in time.

3) General measurement of crimping wire

In electrical equipment, it is often found that individual core crimping wires are not sent to the position, or cannot be locked after being sent to the position, and the contact is unreliable. The reason for the analysis is that there are burrs or dirt on the screw teeth of individual mounting holes. In particular, the last few mounting holes that the factory has installed into a plug socket have to be removed one by one after the defect is found, and the plug socket has to be replaced. In addition, due to improper selection of wire diameter and crimp aperture, or due to misoperation of the crimping process, the crimping end will not be firm. For this reason, the manufacturer shall conduct a general test on all mounting holes of the delivered plug (seat) sample before the finished product leaves the factory, I .e. use the loading and unloading tool to touch and send the crimped wire with pin or socket to the position to check whether it can be locked. Check the pull-out force of each crimped wire according to the product specifications.