Fault Situation Of Drainage And Ditch Clamp

2. Drainage groove clamp fault situation
From the line operation in recent years, the most common fault of the drainage line is the heating and disconnection of the wire joint at parallel groove. According to the operation statistics, there were 2 such accidents in 2012.
At 03:00 on February 20, 2012, the current of phase A of the 35kV Jingnan line was zero. After inspection, it was found that the phase A drainage line of pole #4 was burned 30 cm away from the tension clamp, and the inner wire of parallel groove clamp connector was melted and adhered to the clamp.
At 01:12 on November 28, 2012, the current of phase B of the 35kV Anpan line was zero. After inspection, it was found that the phase B drainage line of pole #2 was melted 30 cm away from the tension clamp, the wire was burned to a certain extent, and the bolts of pg clamp connector were rusted.
3. Drainage pg clamps Failure Analysis
Drainage single bolt parallel groove connector is the weak link of the electrical connection of the transmission line. Due to the continuous change of power load and the change of operating environment temperature, it is easy to fail. Although there are many reasons for the failure, it is mainly caused by the loosening of bolt stress causing the contact pressure to drop; the long-term shaking of the wire causing the contact surface to loosen; severe environmental pollution causing the contact resistance of the drainage joint to increase rapidly; and other reasons such as large fluctuations in line load and improper construction of the drainage joint.