Four factors of pin contact resistance and reliability of RJ45 network transformer

The contact resistance of pin pin pin of RJ45 Internet RF connector is mainly affected by the raw material, vertical pressure, surface shape, applied voltage and current.

1. Contact material

The technical standard of Internet RF connector requires different contact resistance assessment standards for the same specification and model of connector contact made of different materials. Select and buy Ethernet filter to quickly separate the contact resistance of 1mm plug-in contact, alloy copper ≤ 5m Ω, non-ferrous metal ≤ 15m Ω, which is required by general standard gjb101-86 for electrical connector resistant to natural environment.

2. Surface vertical pressure of contact surface

The surface vertical pressure of the contact means the force caused by the contact surface and perpendicular to the contact surface. With the increase of vertical pressure, the total number and total area of contact micro points of miniature network transformer also gradually increase, in addition, the contact micro points connect from ductile deformation to plastic deformation. Because the centralized resistor is slowly reduced, and then the contact resistance is reduced.

The key of contact positive pressure is the geometry appearance and raw material characteristics of the contact.

3. Surface shape

The surface shape includes the appearance of the design concept and the natural environment. The surface of the contact will be a loose surface film caused by the adhesion and accumulation of dust, turpentine, oil stains and other mechanical equipment on the contact surface. This surface film is easy to be embedded in the external economic dent of the contact surface because of the presence of particulate chemicals, which makes the total contact area smaller and the contact resistance larger Extremely stable. The other is the environmental pollution film produced by physical adsorption and organic chemical adsorption. The key to the metal surface is organic chemical adsorption, which is caused by the physical adsorption and the transfer of electronic devices. Therefore, for some commodities with specified sales price, it is necessary to have clean assembly line environment standard, sound cleaning and processing technology and necessary structural sealing measures for micro gigabit network transformers such as aerospace electrical connectors. It is necessary to have excellent storage and application of actual operation natural environment standard for application business.

4. Applied working voltage

When the working voltage is applied to a certain threshold value, the contact film will be hot broken down, and then the contact resistance will be reduced rapidly. However, because the thermoelectric effect accelerates the chemical changes around the film, it has a certain repair effect on the film. Therefore, the resistance value shows the discrete system. In the vicinity of the threshold voltage, the slight fluctuation of the current will cause the current to change within the range of 20 times or dozens of times. Make the contact resistance change a lot. If you don't master this kind of thing, it will lead to incorrect detection and application of the contact.