Deals solely with the condition of steady-state operation of cables at all alternating voltages, and direct voltages up to 5 kV, buried directly in the ground, in ducts, troughs or in steel pipes, as well as cables in air. The term "steady-state" is intended to mean a continuous constant current (100% load factor) just sufficient to produce asymptotically the maximum conductor temperature, the surrounding ambient conditions being assumed constant.Note. Appendix A - Reference ambient temperatures, and thermal resistivities of soils in various countries. Appendix B - Information required from the purchaser for the selection of the appropriate type of cable. Appendix C - Digital calculation of quantities, graphically.

IEC 60287-1-1 Ed. 2.0

IEC 60287-1-2 Ed. 1.0

IEC 60287-2-1 Ed. 1.2

IEC 60287-2-2 Ed. 1.0

IEC 60287-3-1 Ed. 1.1

IEC 60287-3-2 Ed. 1.0

CEI 20-21 Ed. 2 (1988) - Identical