Armored Cable
An armored cable is an electrical or communication cable enclosed in a protective metal layer, typically galvanized steel, aluminum tape, or corrugated steel, providing mechanical strength, crushing resistance, and electromagnetic shielding to protect internal conductors from physical damage, moisture, and environmental hazards.
In manufacturing and asset reliability, armored cables are deployed in harsh industrial environments such as mines, underground plants, and outdoor yards where cables face flying rocks, rat fangs, abrasion, or electromagnetic noise. They serve as Earth Continuity Conductors (ECC) for fault current conduction and eliminate the need for rigid pipe-and-wire installations, offering faster deployment and flexibility in tight pathways.
- Circulating currents in armor wires: Net currents in single-core armored cables cause eddy current and hysteresis losses, leading to overheating and reduced efficiency if non-magnetic materials like copper or aluminum wire armor are not used.
- Corrosion at bend points: Repeated pulling stress or undue bending at termination points causes armor wire wear, corrosion, and cracking, compromising structural integrity and moisture resistance.
- Termination difficulties: Metallic armor’s weight and stiffness lead to improper grounding or severing during installation, causing floating armor that fails to act as an ECC, increasing electrical hazard risk.
Why does steel tape armor have higher compressive strength than non-armored cables?
Per IEC 60502-2, steel belt armor disperses impact energy, achieving 3–5× higher compressive strength by providing rigid body defense and stress bearing.
What is the ECC function of armor?
Armor acts as an Earth Continuity Conductor, providing effective conductance for earth fault currents to ensure safety and system grounding.
When is polymeric armor superior to metallic armor?
Polymeric armor offers 5× better impact performance and equivalent fluid protection while reducing weight, stiffness, and termination complexity.