On April 12, the 10kV underground cable of Wuhan Jiaotong school broke down, resulting in power failure and darkness in all student dormitories. As the direct buried cable is adopted in the campus, the cable direction in the campus is complex, and the two units previously contacted by the school failed to find the cable fault point, so they had to rent the power generation equipment for emergency power supply at a high price (Fig. 1).
At 19:40 on the same day, our technicians received the emergency repair call from the school, immediately organized the cable fault location equipment to be transported to the site for on-site environmental investigation and equipment commissioning, and started work at 21:30. The technicians orderly used the high-precision cable fault test equipment produced by our company for emergency repair.
1. Use ZC-430B insulation resistance tester to test the faulty cable and judge that it is a high resistance fault;
2. ZC-700B cable fault tester is used for low-voltage pulse method test, and the total length of the cable is 2.2km;
3. ZC-501A high-voltage generator and high-voltage capacitor are used to pressurize and discharge the cable, and kst-700b cable fault tester is tested by charge flash method to obtain the fault distance of 950m (Fig. 2);
4. Use ZC-704 all digital Pathfinder to obtain the path direction of directly buried cables in the campus and roughly judge the distance of 950m (Fig. 3);
5. 20m before and after 950m, use ZC-705B acoustic magnetic synchronous precise locator to listen, check the discharge along the way, and finally lock the cable fault point (Fig. 4).
Fig. 2 cable fault location Figure 3 finding cable fault points Figure 4 locking fault point
After the professional and careful test, listening and analysis of our technicians, we finally found the fault point at the viaduct approach at the school gate at 1:00 a.m. in the morning. We can quickly and accurately explore such hidden and complex cable fault points. In addition to the professional and experience of our technicians, we are also inseparable from our production: ZC-430B digital insulation resistance tester, ZC-700B multi pulse cable fault tester host ZC-704 all digital Pathfinder with compass indication, ZC-705B acoustic magnetic synchronous locator, ZC-501 high voltage generator and other high-precision cable fault testing equipment are "Heroes behind the scenes", which make us no longer afraid of any hidden and complex cable fault. They are a good helper for us to find the cable fault point, so that we are not confused on the way to locate the cable fault point.
Early the next morning, our company had completed the cable repair and voltage withstand test for the school, and the school was also impressed by the professional skills and responsible attitude of our technicians; A good horse also needs a good saddle. Our safe, efficient and accurate cable fault tester is a powerful helper in practical work. Our company will continue to provide customers with excellent products and high-quality services.
