Abstract
The power cables passing through penetration leads to growth of the thermal ageing mechanisms rate. The paper presents the results of the laboratory tests when the real environmental service conditions for penetration are simulated comparison with the result of the thermal computation of the power cables heating and of the temperature influence evaluation of temperature increase of the power cable components on the cable lifetime. For this particular case, a power cable with PVC insulation, we estimated a lifetime decrease about 20 years referring to lifetime (30÷40 years) for location in air.