Uo/U (Um) System Type
Three-phase alternating curent Single phase alternating curent
Both phase conductor insulated In earthed single-phase conductor
Rated Voltage Permissible max. operating voltages Rated Voltage Permissible max. operating voltages Rated Voltage Permissible max. operating voltages
Un Ub max. Un < 2 Uo Ub max. Un < Uo Ub max.
kV kV kV kV kV kV kV
0.6/1 (1.2) 1 1.2 1.2 1.4 0.6 0.7
1.8/3 (3.6) 3 3.6 3.6 3.8 1.8 2.0
3.6/6 (7.2) 6 7.2 7.2 8.3 3.6 4.1
6/10 (12) 10 12 12 14 6 6.7
8.7/15 (17.5) 15 17.5 17.5 20.2 8.7 10.1
12/20 (24) 20 24 24 28.0 12.0 14.0
18/30 (36) 30 36 36 42 18 21
20.3/35 (42) 35 42 40.6 47.3 20.3 23.7
26/45 (52) 45 52 - - - -
38/66 (76) 66 76 - - - -
64/110 (123) 110 123 - - - -
76/132 (145) 132 145 - - - -
89/154 (175) 154 175 - - - -