[email protected]

Dynamic Application

42 Min Read
The (N)TSCGEWÖU 3x50+3x25/3 12/20kV reeling cable has a base ampacity of approximately 210 amperes when installed in free air with standard ambient conditions of 30°C (86°F) and conductor temperature not exceeding 90°C. However, when this same cable is wound in a 3-layer configuration on a cylindrical motorized reel drum—a typical arrangement for port cranes, ship-to-shore gantries, mining equipment, and mobile cargo handling systems—the effective ampacity is dramatically reduced through application of the DIN VDE 0298-4 thermal derating factor of 0.49. This produces a practical continuous ampacity of approximately 102.9 amperes (calculated as 210 A × 0.49), representing less than half the free-air capacity. The cable features three 50 mm² main phase conductors and three 25 mm² grounding conductors arranged in a compact helical geometry, with an outer diameter of approximately 52–58 mm and total weight of approximately 4,300–4,600 kg/km. The derating factor reflects the fundamental thermal reality that cable layers wound inside the drum cannot radiate heat to the surrounding air, trapping thermal energy and forcing the cable to operate at temperatures significantly above the ambient reference condition.
Technical Department
on28/02/2026

Derating Factors: Current Carrying Capacity of (N)TSCGEWÖU 3×50+3×25/3 12/20kV Wound in 3 Layers on a Reel

The (N)TSCGEWÖU 3×50+3×25/3 12/20kV reeling cable has a base ampacity of approximately 210 amperes when installed in free air with standard ambient conditions of 30°C (86°F) and conductor temperature not exceeding 90°C. However, when this same cable is wound in a 3-layer configuration on a cylindrical motorized reel drum—a typical arrangement for port cranes, ship-to-shore gantries, mining equipment, and mobile cargo handling systems—the effective ampacity is dramatically reduced through application of the DIN VDE 0298-4 thermal derating factor of 0.49. This produces a practical continuous ampacity of approximately 102.9 amperes (calculated as 210 A × 0.49), representing less than half the free-air capacity. The cable features three 50 mm² main phase conductors and three 25 mm² grounding conductors arranged in a compact helical geometry, with an outer diameter of approximately 52–58 mm and total weight of approximately 4,300–4,600 kg/km. The derating factor reflects the fundamental thermal reality that cable layers wound inside the drum cannot radiate heat to the surrounding air, trapping thermal energy and forcing the cable to operate at temperatures significantly above the ambient reference condition.
19 Min Read
When a reeling cable passes over a sheave, pulley, or diverter roller during normal operation, it undergoes mechanical bending that imposes significant stress on its internal conductors and insulation layers. Unlike a cable running in a straight line, where tension is distributed relatively evenly, a cable wrapped around a curved surface experiences localized compression and tension that can cause permanent deformation, insulation cracking, and conductor fatigue within surprisingly short timeframes if the geometry is not carefully controlled.
Technical Department
on26/02/2026

Change of Direction: Managing Bending Stress in Reeling Cables

When a reeling cable passes over a sheave, pulley, or diverter roller during normal operation, it undergoes mechanical bending that imposes significant stress on its internal conductors and insulation layers. Unlike a cable running in a straight line, where tension is distributed relatively evenly, a cable wrapped around a curved surface experiences localized compression and tension that can cause permanent deformation, insulation cracking, and conductor fatigue within surprisingly short timeframes if the geometry is not carefully controlled.
22 Min Read
A bucket wheel excavator is a remarkable piece of mining equipment: a massive rotating wheel fitted with buckets that continuously scoops material from a mining face, lifts it high into the air, and deposits it onto a conveyor system. The electrical cables that power such equipment face challenges that are fundamentally different from the cables used in stationary equipment or even in traditional draglines and shovels. As the main bucket wheel rotates continuously — sometimes for 12 to 20 hours per day — the flexible power cables that deliver electricity to drive motors must rotate with the wheel while simultaneously being wound and unwound through the cable reel system that connects the mobile equipment to the fixed power supply. This simultaneous rotation and reeling creates torsional stress — twisting force — that attempts to spiral the cable around its own axis. A standard single-sheath cable, designed primarily to withstand tension and bending, will gradually degrade under this torsional loading, with internal conductors ultimately fracturing and failing. A properly designed double-sheath cable with an anti-torsion braid can withstand decades of this continuous torsional punishment without degradation. Understanding why this distinction matters is the key to extending cable life and preventing expensive equipment failures.
Technical Department
on26/02/2026

(N)TSKCGEWÖU Double-Sheath Design: Why Anti-Torsion Braid is Critical for Bucket Wheel Excavators

A bucket wheel excavator is a remarkable piece of mining equipment: a massive rotating wheel fitted with buckets that continuously scoops material from a mining face, lifts it high into the air, and deposits it onto a conveyor system. The electrical cables that power such equipment face challenges that are fundamentally different from the cables used in stationary equipment or even in traditional draglines and shovels. As the main bucket wheel rotates continuously — sometimes for 12 to 20 hours per day — the flexible power cables that deliver electricity to drive motors must rotate with the wheel while simultaneously being wound and unwound through the cable reel system that connects the mobile equipment to the fixed power supply. This simultaneous rotation and reeling creates torsional stress — twisting force — that attempts to spiral the cable around its own axis. A standard single-sheath cable, designed primarily to withstand tension and bending, will gradually degrade under this torsional loading, with internal conductors ultimately fracturing and failing. A properly designed double-sheath cable with an anti-torsion braid can withstand decades of this continuous torsional punishment without degradation. Understanding why this distinction matters is the key to extending cable life and preventing expensive equipment failures.
24 Min Read
Rail-mounted gantry (RMG) cranes are the largest and most powerful material handling systems in modern container ports and intermodal yards. Unlike traditional spreader cranes that hang from a fixed trolley, RMG cranes are completely self-contained electromechanical systems mounted on wheels that roll along parallel steel rails, spanning the entire width of a container yard. The electrical architecture of an RMG is fundamentally different from other port equipment, and this difference cascades into specific requirements for power transmission cables. RMG是现代集装箱港口最大最强的物料搬运系统。其完全自推进的电气架构对电缆提出了特殊要求。
Technical Department
on26/02/2026

Rheyfirm® (RS) 20kV: Migration Strategy for RMG Crane Cable Replacement

Rail-mounted gantry (RMG) cranes are the largest and most powerful material handling systems in modern container ports and intermodal yards. Unlike traditional spreader cranes that hang from a fixed trolley, RMG cranes are completely self-contained electromechanical systems mounted on wheels that roll along parallel steel rails, spanning the entire width of a container yard. The electrical architecture of an RMG is fundamentally different from other port equipment, and this difference cascades into specific requirements for power transmission cables. RMG是现代集装箱港口最大最强的物料搬运系统。其完全自推进的电气架构对电缆提出了特殊要求。