In this paper, the steady state current rating calculations for 3-phase XLPE distribution power cables are performed using an analytical set of thermal equations. The analysis is made for different installation configurations (direct burial and tube installations) under various possible extreme Finnish environmental conditions. This study will enable electric power utilities to revise allowable current ratings to avoid damage to their power cables as well ensure safe and reliable distribution of power to the customers in the future smart grid environment. Ill. 6, bibl. 9, tabl. 5 (in English; abstracts in English and Lithuanian).