What is the purpose of a stress cone on underground cable?

The purpose of a stress cone on underground cable is to spread out the tracking area and dissipate electrical stress. Stress cones are specifically designed to manage electrical stress concentration that can occur at the termination points of high-voltage cables. When high voltage is present, electric fields can be concentrated at the point of abrupt changes in geometry, such as cable terminations. The stress cone creates a gradual transition in the electric field, helping to prevent dielectric breakdown, which can lead to insulation failure.

By providing a more uniform electric field distribution, the stress cone mitigates the risk of arcing and extends the service life of the cable. This is crucial for maintaining reliability in underground power distribution systems, where safety and performance are top priorities.

While insulation, mechanical strength, and installation considerations are important aspects of underground cable design and function, the primary role of a stress cone focuses on managing electrical stress rather than enhancing these other aspects directly.