How do you calculate the maximum tensile load or suspension length of a copper cable?
Up to a maximum of 1000 N, the operational tensile strain for all cables and wires is calculated as 15 N of tensile load for each mm² of cross-sectional copper area. It is irrelevant whether the cables or wires employed have a solid or flexible conductor, or whether they are intended for fixed or flexible use. During laying or installing of solid conductor core cables, such as NYY for fixed installations, a factor of 50 N/mm² can be used.
Example calculation of maximum tensile load for an ÖLFLEX® CLASSIC 100 5 G 10 mm² (stranded flexible conductor) in operation:
Total copper cross-section: 5 cores x 10 mm² = 50 mm²
Tensile load in Newton: 50 mm² x 15 N = 750 N
Tensile load in kilograms: 750 N : 10 = 75 kg
Calculation of the resulting max. vertical cable suspension length:
Cable weight, version 5 G 10 mm²: 792 kg = 1000 m
Cable length, version 5 G 10 mm²: 75 kg = ??? m
Max. suspension length: (75 x 1000) : 792 = 94.7 m
If a cable features a separate support element, the maximum tensile load specified on the relevant catalogue page applies. Support elements are also required if a lamp, device or control console is to be affixed to a free-hanging cable. In this case, it must be ensured that the combined weights of the cable and the lamp or device do not exceed the maximum recommended tensile strain!
The mechanical tensile strain or force is measured in Newton (N).