RJ45 interface, also known as crystal plug, is an important component of the information socket (i.e. communication outlet) connector in the wiring system. It consists of a plug (often referred to as a connector or crystal head) and a socket (i.e. RJ45 module). The plug design has 8 grooves and 8 contacts, which work together with the socket to form a complete connector unit. This type of connector is widely used in the network equipment connection between LAN and ADSL broadband internet users, and the network cable used is often referred to as a fifth level line or twisted pair.
In the performance of RJ45 connectors, the contact resistance and reliability of PIN pins are important indicators for measuring their quality. The following are the main factors that affect these two points:
1、 Selection of connector contact material:
The technical standards for RJ45 connectors set differentiated contact resistance assessment standards for the same specification plug-in contacts made of different materials. Taking the general specification GJB101-86 for quick separation and environmental resistance RJ45 connectors as an example, for plug-in contacts with a diameter of 1mm, the contact resistance of copper alloy material should not exceed 5m Ω, while that of iron alloy material should be controlled within 15m Ω. This fully demonstrates that material selection has a significant impact on contact resistance.
2、 Vertical pressure on the contact surface of the connector:
Surface vertical pressure refers to the force generated on the contact surface perpendicular to the contact surface when RJ45 connector contacts each other. As the vertical pressure increases, the number and area of contact micro points also increase accordingly, and the contact micro points gradually transition from elastic deformation to plastic deformation. During this process, the concentrated resistance gradually decreases, resulting in a decrease in contact resistance. The magnitude of the contact positive pressure mainly depends on the geometric shape of the contact piece and the properties of the material used.
3、 Surface cleanliness of contact parts:
During the use of RJ45 connectors, a loose surface film may form on the contact surface due to mechanical adhesion of dust, oil, and other substances. The particulate matter contained in this layer of film is easily embedded in the micro pits on the contact surface, leading to a reduction in contact area, an increase in contact resistance, and an extremely unstable contact state. Therefore, for products that require extremely high reliability, such as medical connectors, it is necessary to ensure that their assembly production environment, storage environment, and operating environment are all kept highly clean.
