Generally speaking, people still have many doubts and worries about the conductivity of insulated piercing clamps. Can such a few small spurs withstand such a large current? Especially in today's era of rapid economic development in my country, with the rapid increase in electrical capacity, can the insulation piercing clamp bear such a heavy task?　　 Next, we will analyze the working principle of the parallel channel clamp and the insulation piercing clamp from the principle of conducting current between conductors.　　The current conduction between conductors can be analyzed from two aspects: the mechanical contact area of the conductor and the current conduction path.　　1. The mechanical contact area of the conductor　　 From a microscopic point of view, the surface of a conductor is composed of countless uneven peaks and valleys. The smoother the surface of the conductor, the smaller the height difference between the peaks and valleys. When two conductors are brought into contact by an external force, the contact is mainly in the form of peak-to-peak contact. Therefore, the actual mechanical contact area is much smaller than the nominal contact area of the clamp design. According to literature analysis, the real mechanical contact area is about 7% of the nominal contact area.　　 2. Current conduction path between conductors 　　 1. Under the action of external pressure, the active aluminum oxide (Al2O3) layer on the aluminum-aluminum interface of the two conductors is squeezed or rubbed, causing it to partially rupture, allowing aluminum electrons to flow freely between the surface peaks and peaks to form a certain degree of electrical conductivity. ability. The greater the pressure, the more peak-to-peak points of contact and the lower the contact resistance.  2. Activated aluminum oxide (Al2O3) itself has electrical conductivity, so that the undamaged area also has a certain electrical conductivity.　　3. Due to the good plasticity of aluminum, when the two interfaces are in pressure contact, part of the aluminum in the inner wall of the clamp will be plastically deformed and enter the stranded void of the outer layer of the wire, increasing the effective contact area and infiltration between molecules. More active, as the number of aluminum atoms in the oxide layer further increases, the electrical conductivity on the electrical interface is improved.　　Due to the creep of the wire, the wire is slightly thinner, the diameter is reduced, the effective contact area is reduced, and the resistance of the groove clamp is increased. The reduction in the effective contact surface is mainly due to the reduction in the pressure of the wire clamp on the wire and the aggravation of the oxidation of the contact surface.　　 Therefore, in order to improve the power supply reliability of the parallel groove clamp, multiple parallel groove clamps are often used on site, as shown in Figure 1-25. Therefore, we usually think that the parallel groove splint plate contact is actually only point-to-point contact, and the puncture clamp pierces the wire against the blade, as if a finger is inserted into the water. According to relevant literature, its contact area is more than that of the parallel groove line. The clip is more than 1 times larger. Moreover, the puncture clamp has the advantages of convenient installation and high reliability.　　 The wire pierced by the insulated piercing clamp should ensure that its breaking force is not less than 95% of the original wire's breaking breaking force, and the wire cannot lose its mechanical properties due to the puncture.