flexible mining cable specifications

The (N)SSHÖU 3×50+3×25/3 1.1/1.1kV trailing cable represents far more than a simple voltage specification change from the standard European 0.6/1kV industrial flexible cable. When you examine New Zealand’s mining, quarrying, and port operations, the environment is fundamentally different from European industrial applications. The country’s open-cast mining sites experience extreme weather variations, high UV radiation, exposure to harsh corrosive mining chemicals, and require continuous mechanical durability in equipment that cannot afford operational downtime. New Zealand’s electrical safety standards reflect this demanding reality through three core requirements. First, the nation’s IT earthing system (isolated or high-resistance grounding) demands insulation rated for phase-to-earth voltage equal to phase-to-phase voltage (Uo = U), which necessitates the 1.1/1.1kV rating instead of 0.6/1kV. Second, the split symmetrical earth design with three individual 25mm² earth conductors placed symmetrically around the three 50mm² phase conductors provides unprecedented protection against unbalanced fault conditions that could otherwise result in lethal contact voltage hazards for equipment operators. Third, New Zealand’s mining operations often involve long-distance power transmission—sometimes exceeding 800 meters from the surface substation to the underground working face—which creates severe voltage drop problems that cannot be adequately addressed by 0.6/1kV systems but are managed effectively by the higher 1.1/1.1kV rating. The (N)SSHÖU 3×50+3×25/3 1.1/1.1kV cable delivers a total weight of approximately 3550 kilograms per kilometer, carries a copper content of 1680 kg/km, maintains an ampacity of 182 amperes in free air at 30°C, features an outer diameter in the range of 42.0 to 47.0 millimeters, and is constructed from EPR rubber insulation with a heavy-duty CPE outer sheath specifically formulated to resist the abrasion, tearing, oil penetration, and ultraviolet degradation characteristic of New Zealand’s unforgiving mining and quarry environments.