RHEYFIRM® (S) series reeling cables with 3+3 core distributed earth design exhibit outer diameters ranging from approximately 40.0 mm (for 3×25+3×25/34 mm² configurations at 6/10 kV) to 76.0 mm or larger (for heavy-duty 3×185+3×95/35 mm² configurations at 12/20 kV). The nominal outer diameter depends on the specific conductor cross-section, voltage rating, and insulation thickness selected. For a typical medium-voltage marine and industrial application, a RHEYFIRM® (S) cable rated 3×70+3×35/32 mm² at 6/10 kV exhibits an outer diameter between 52.0 mm and 56.0 mm with approximate total cable weight of 4,300 kg/km (2,890 lbs/1000ft), while the corresponding 12/20 kV variant reaches 62.0 to 67.0 mm outer diameter with weights near 6,800 kg/km (4,570 lbs/1000ft).

on03/03/2026

RHEYFIRM® (S) 3+3 Core Design: Why Does Nexans Use Distributed Earth in the (S) Series and How Does It Affect EMC?

RHEYFIRM® (S) series reeling cables with 3+3 core distributed earth design exhibit outer diameters ranging from approximately 40.0 mm (for 3×25+3×25/34 mm² configurations at 6/10 kV) to 76.0 mm or larger (for heavy-duty 3×185+3×95/35 mm² configurations at 12/20 kV). The nominal outer diameter depends on the specific conductor cross-section, voltage rating, and insulation thickness selected. For a typical medium-voltage marine and industrial application, a RHEYFIRM® (S) cable rated 3×70+3×35/32 mm² at 6/10 kV exhibits an outer diameter between 52.0 mm and 56.0 mm with approximate total cable weight of 4,300 kg/km (2,890 lbs/1000ft), while the corresponding 12/20 kV variant reaches 62.0 to 67.0 mm outer diameter with weights near 6,800 kg/km (4,570 lbs/1000ft).

In port machinery, material handling equipment, stacker-reclaimers, festoon systems, and industrial cranes operating at speeds up to 240 meters per minute, trailing cables experience a distinctive and punishing stress pattern called reverse S-bending. The cable is not simply bent in one direction — it repeatedly curves left, then right, then left again, following the path of the equipment as it traverses an S-shaped trajectory or as cable spools alternately bend the cable in opposite directions during reeling and unreeling cycles. This reverse bending motion is fundamentally different from the static or single-direction bending challenges faced by underground mining cables or fixed installations. The cable experiences rapid alternation between tensile and compressive stress on its individual conductors, combined with torsional (twisting) forces that attempt to unwind the cable's spiral structure. For a standard cable, this combination of stresses creates a perfect recipe for premature fatigue failure, conductor breakage, and insulation degradation.

Technical Department

on26/02/2026

S-Bend Fatigue: Why (N)TSKCGEWÖU Lasts Longer in High-Speed Applications

In port machinery, material handling equipment, stacker-reclaimers, festoon systems, and industrial cranes operating at speeds up to 240 meters per minute, trailing cables experience a distinctive and punishing stress pattern called reverse S-bending. The cable is not simply bent in one direction — it repeatedly curves left, then right, then left again, following the path of the equipment as it traverses an S-shaped trajectory or as cable spools alternately bend the cable in opposite directions during reeling and unreeling cycles. This reverse bending motion is fundamentally different from the static or single-direction bending challenges faced by underground mining cables or fixed installations. The cable experiences rapid alternation between tensile and compressive stress on its individual conductors, combined with torsional (twisting) forces that attempt to unwind the cable’s spiral structure. For a standard cable, this combination of stresses creates a perfect recipe for premature fatigue failure, conductor breakage, and insulation degradation.