护套线过电流诱发短路故障起火过程及痕迹特征

为深入研究RVVB护套线发生过电流诱发短路故障的火灾危险性,搭建RVVB护套线过电流诱发短路故障电路实验平台,探究短路故障起火过程及痕迹特征,对过电流诱发短路故障初次短路发生时间、起火特征及痕迹特征进行研究.结果表明:当I≥45 A时,护套线会出现短路击穿现象,并引发明火燃烧;当I=66 A时,过电流诱发短路故障平均时...

The process and trace of cables breakdown induced by overcurrent

In order to study the fire risk of short-circuit fault caused by overcurrent of electric RVVB wire, this paper built a test platform for RVVB wire overcurrent induced short-circuit faults, and studied the fire process and trace of short circuit fault. The initial short circuit occurrence time, combustion characteristics and trace characteristics when the RVVB wire was short-circuited were studied. The results showed that when I≥ 45 A, the RVVB wire will appear short circuit breakdown phenomenon and cause open fire combustion; When I= 66 A, the average time of short-circuit fault induced by over-current is shortened from 1 803.4 s of I=45 A to 52.8 s, and the combustion time of open fire fluctuates from 16.4 s to 28.96 s, which increases the fire risk; The short-circuit fault induced by overcurrent in the RVVB wire will produce arc fusion marks such as sphere shape, semicircle shape, pointed shape, joint shape, pit shape, fracture shape,and overlapping shape, as well as splashing fusion marks with different diameters.The research results can provide a theoretical basis for the ignition mechanism of short circuit fault induced by over-current and the identification of weld marks.