Steel wire armoured cable, commonly known as SWA cable, is a robust power cable designed for mains electricity supply in demanding environments. Featuring a layer of galvanized steel wires wrapped around insulated conductors, steel wire armoured cable provides exceptional mechanical protection against impact, crushing, and environmental hazards. Ideal for direct burial and outdoor use, SWA cables are widely used in underground power distribution, industrial sites, and infrastructure projects where safety and durability are paramount.

1. What is Steel Wire Armoured Cable (SWA)?

Steel wire armoured cable (SWA) is a multi-core power cable reinforced with galvanized steel wire armouring under an outer sheath. Rated at 600/1000V, it excels in low-voltage applications requiring mechanical strength. Unlike standard cables, SWA's armour shields inner cores from physical damage, making it perfect for harsh conditions like underground laying or exposed industrial runs.

2. Construction and Key Components

Typical SWA structure includes:

• Conductor: Stranded copper (Class 2 per BS EN 60228).
• Insulation: XLPE or PVC for electrical isolation.
• Bedding: PVC layer cushioning cores from armour.
• Armour: Galvanized steel wires for mechanical protection (SWA).
• Sheath: Black PVC or LSZH for UV/moisture resistance.

This layered design ensures steel wire armoured cable withstands tensile stress during installation and operation.

3. Primary Applications of Steel Wire Armoured Cable

Steel wire armoured cable shines where unarmoured cables fail:

• Underground power networks and direct burial (min. 450-600mm depth).
• Outdoor lighting, street power, and utility infrastructure.
• Industrial sites: Factories, warehouses, construction areas.
• Outbuildings, generators, and railways.
• Harsh environments: Rodent-prone, high-traffic, or seismic zones.

4. Standards and Certifications

Key standards for steel wire armoured cable:

5. Advantages and Benefits

• Superior mechanical protection against crushing/impact.
• Direct burial capability without conduits.
• Armour can serve as CPC (earth) if sized correctly.
• Long lifespan (30+ years) in harsh conditions.
• Cost-effective for high-risk installs.

6. Safety Tips and Precautions

Handling steel wire armoured cable safely prevents injuries and faults:

• Use certified SWA (BASEC/VDE) to avoid counterfeits.
• Earth armour properly per BS 7671 Table 54.7.
• Wear PPE: Gloves, eye protection for stripping.
• Avoid single-core SWA (use AWA to prevent overheating).
• Inspect for damage before/after install; test insulation (>1 MΩ).
• LSZH variants for enclosed/public spaces to reduce fire smoke.

7. Installation Best Practices

• Bury at 450mm+ depth; use warning tape above.
• Maintain min. bend radius (8-12x diameter).
• Use brass/metal glands to secure armour.
• Strip with SWA tools to avoid core damage.
• Test continuity, RCD trips post-install.

8. SWA vs AWA Cable

9. Final Thoughts

Steel wire armoured cable is indispensable for reliable power in tough settings, offering unmatched protection and safety. Follow standards and precautions for optimal performance and hazard-free use.

Need quality steel wire armoured cable? Contact Henan Province Jianyun Cable Co., Ltd. for BS/IEC-compliant SWA solutions.