Self-complex fuse is a new type of polymer positive temperature coefficient over-current protection components, circuit can be short-circuit and overload protection, unlike the traditional fuse is, since the complex fuse in the fault removal and power cut, can be automatically restored, no need to replace. Fuse Compared with the traditional fuse has many advantages, in this paper, combined with the application of self-complex fuse in the field of industrial automation instrumentation control and civil applications, this paper introduces the advantages and disadvantages of self-complex fuse, the action principle of self-complex fuse and the selection method of self-recovery fuse.
Formerly electronic equipment, instrumentation using traditional fuses for overcurrent protection, but only can be protected once, burn off must be replaced, Fuse but also will appear fuse abnormal burn conditions, such as start-up moments, unplug devices, bad contact, the use of fuse time too long, will lead to fuse burning. Fuse should be replaced in accordance with the provisions of the same specifications, but in the industrial scene often have what fuse on the case of what fuse, and caused by the wrong replacement, sometimes because the fuse specification is too large, the fault caused by the current of the electronic equipment to burn the components, causing failure to expand the accident occurred.
Self-complex fuses are mainly composed of specially treated polymeric resins (polymer) and conductors, in the normal state, the polymer tightly binds the conductor to the crystalline structure, Fuse forming a low impedance chain lock, because the impedance is only dozens of ohms, although the current passes through the self complex fuse, but the heat produced is very small, Without changing the crystalline structure of the polymer, when the abnormal current occurs, the heat produced on the conductor will turn the polymer grains from crystallization to colloidal form, at this time, the conductor bound in the polymer will be separated, causing the resistance to rise rapidly, Fuse limiting the abnormal current flow through the self-recovery fuse.