1.3(1.3) Rated voltages The normalized values of the rated voltages UqIU (Um) of the cables according to this standard are lis ed in table 1. The rated voltages of a cable consis of a combination of three alternating voltages Uü/U (Um), where: t/o is the assigned voltage between the conductor and the earth screen. This voltage serves as the basis for determining the test voltages; U is the assigned voltage between any two conductors of a multi-core cable or of a system of single-core cables; Um is the maximum value of the highest mains voltage for which the cable may be used (see IEC publication 38). The values of the alternating voltages are effective values (50 or 60 Hz). Table 1 - Assigned voltages maximum value of the duration of single-phase closures in the network highest < 8 hours/time or > 8 hours/time or mains voltage < 125 hours cumulative/year > 125 hours cumulative/year assigned voltages U0/U kV kV 7, 2 3.6/ 6 6 /10 12 6 /10 8.7/15 17.5 8.7/15 12 /20 24 12 /20 18 /30 36 18 /30 - Note The values of U{)IU and Um are taken from IEC publication 38 (6th edition, 1983) and from IEC publication 183 (2nd edition, 1984). The voltages U{] and U may be exceeded indefinitely by 10% and briefly by 20% during normal operation.
NEN 3620-1989 history
1989NEN 3620-1989 Cables with insulation of cross-linked polyethylene for voltages of 6 kV up to and including 30 kV