Contact Failure Caused By Surface Defects In Cable Terminals

The pores on the terminal lugs surface were identified as weak points in the electrical insulation. These tiny pores, under high voltage or pulsed voltage, can cause abnormally high local electric field strength, becoming the initiation points of discharge channels.

In the power system, copper lugs carries the core function of conductor connection. When pores exist on surface Aluminum Cable Lug, the electric field distribution around them is not uniform. Current density concentrates around the pores, causing this area to experience higher electrical stress. This asymmetrical voltage distribution causes the pores to gradually evolve into creepage paths. When liquid contaminants or moisture enter the pores of Compression Cable Lug, the conductivity changes, enabling surface discharge to be initiated.