Use characteristics of cable
(1) the rated voltage Uo/U is 0.6/1kV.
(2) the highest rated temperature of cable conductor is 70 C.
(3) the maximum temperature of cable conductor is not more than 160 degrees when the short circuit is not longer than 5S.
(4) the ambient temperature of cable laying should not be less than 0 C, and the minimum bending radius is as follows:
Main technical parameters of cable
Calculation conditions of cable carrying capacity
Ambient temperature: it is laid at 40 C in air and buried at 25 C.
Working temperature of cable conductor at 70 degrees centigrade
When the cable is buried, the coefficient of soil thermal resistance is g=1.0. M/W. But the phenomenon of the increase of soil thermal resistance coefficient is not taken into account in the long term operation of the cable due to the migration of water.
When the cable is buried, the distance between the cable axis and the ground is 700mm.
Many cables are laid flat, and the axis of the cable is S=2D.