Description: The cable line fault indicator is installed in the box changes, cable branch box, ring network cabinets, cable fault indicating devices branch. Indicating a fault current passing means for. Once the line short-circuit fault line patrol officers can take advantage of flash alarm indicator on the display to quickly determine the fault section, branch and point of failure. Completely change the past blindly transmission line, power transmission sub-closing test to find fault backward approach, greatly improve work efficiency, effectively shortening the outage time, and improve supply reliability and economic efficiency. First, the cable line fault indicator short circuit fault criterion (1) 1t≥600A 1t current starting value for the amount of mutation (2) △ ??1≥0.510 △ 1 current rate of change of 10 for the first short-circuit line current (2) 1 = 01 after line fault current (4) 0.02S≤ △ T≤2S △ T is the current time of the cable line mutation fault indicator, the standard configuration for each of the three short-circuit indicator, short circuit fault indicator to detect a short circuit can detect short-circuit fault . Second, cable line fault indicator Technical parameters: short-circuiting operation response time: 0.02s≤T≤4S, working environment range: -40 ℃ - + 85 ℃ Power supply: Built-in 2000 mA / h lithium a life 5 years, the voltage of 3V automatic reset time: 17 hours handling pretentious simple: require special installation tools can be charged loading indicator. Line Range: Cable Diameter (with skin) ≤ ￠ 40mm cable line fault indicator is installed in the box changes, cable branch box, ring network cabinets, cable fault indicating devices branch