In most power grid operations, when a device or line has a short-circuit fault, an excessive current will be generated in the fuse located under the transformer, causing the fuse in the fuse tube to be disconnected.
When the fault occurs, the breakpoint of the fuse is too close, the arc cannot be extinguished, and the paper tube is easily burned out, which is also the main reason for the burnout of the paper tube of the #dropoutfuse. The main reason for the high failure rate is that the paper tube of the dropout fuse is burned out.
Therefore, in order to solve this problem, we need a drop-type fuse that can avoid the burnout of the fuse tube caused by arcing at the fuse break. This new drop-out fuse and its fuse replacement method has the following features compared to what most power grids are using:
1. Since it includes the insulator guide rod, the drainage conductive bar, the arc extinguishing tube, the connecting plug of the upper melting tube, and the connecting piece of the melting tube of the lower moving contact. A fuse with melt is arranged in the arc extinguishing tube, a blocking rod is arranged near the lower end of the arc extinguishing tube, and a tension spring is hung on the blocking rod, a fixing frame with a hanging ring is fixed on the fuse at the lower end of the melt, the upper end of the tension spring is hung on the hanging ring. When the loop current is greater than the fusing value of the fuse and the fuse is blown, the fuse below moves down rapidly under the action of the tension spring. Fuse point separation and instant arc extinguishing avoid the problem of paper tube burning due to the fact that the breakpoint is too close to the arc and cannot be extinguished. Thereby reduce the line running costs. The blown fuse and the tension spring are in the arc extinguishing tube, which avoids failures such as short circuit of other lines caused by the fuse falling out of the fuse tube caused by other methods. Moreover, the time required to replace the #dropoutfuse is 2 hours, and the time to replace the fuse is 10 minutes, which greatly reduces the labor cost.
2. Since there is a certain distance between the blocking rod and the lower end of the arc extinguishing tube, a pull rope is provided on the hook at the lower end of the tension spring, and the other end of the pulling rope extends out of the lower end of the arc extinguishing tube, which is convenient for the removal of used fuse link and installation of new fuse link.
3. After the upper and lower ends of the fuse link are connected, the tension of the tension spring is 0.4-0.6 N, this will not cause the loop current to be less than the fusing value of the fuse link and cause the fuse to be pulled off, but also ensure that the fuse point is quickly pulled away.