Behavior of Chosen Environmentally Influenced Electrical Cables

The main role of cable sheath is to protect the cable cores from external degradation factors such as water, moisture, mechanical stress, various types of radiation, etc. Its aim is to ensure trouble-free operation and long service life of cable routes, which currently reaches 40–50 years. The composition and properties of sheathing compounds are modified with various admixtures to improve their resistance to external degradation. In real practice, we often encounter cables placed in environment that is not suitable in terms of their declared properties, which can ultimately lead to their damage and shortening of their predicted service life. This paper presents results from the measurements of dielectric parameters, insulation resistance, dissipation factor and breakdown voltage, and mechanical parameters, tensile strength and elongation at break of the cable sheaths. The samples were commercially produced low-voltage cables made from HFFR blends with and without UV stabilization. The influence of natural environment after two years of natural aging in an unprotected outdoor environment was investigated. We accent that while dielectric properties of insulating polymeric materials applied in the cable structure could be convenient, but already two years long exposure to natural environment influence could threaten with important shortening the lifetime.