What is the Difference Between STA Cable and SWA Cable？

Sep. 10, 2025

STA( Steel Tape Armored) and SWA (Steel Wire Armored) Cables are both armored power cables, designed for mechanical protection, but they differ in armor construction and applications:

I. Basic Types of STA Cables and SWA Cables

● STA Cables use single or double-layer steel tapes wrapped around the insulation, providing moderate protection against crushing and rodent damage.

● SWA Cables use steel wires as the cable's reinforcing component, offering higher tensile strength and resistance to bending stresses;

II. Environmental Stress

STA Cables are lighter, making them suitable for underground installations with less mechanical stress, vulnerable to moisture and UV exposure.

SWA Cables have a greater number of steel wires, therefore SWA Cables are more robust and suitable for direct burial or harsh environments where tensile strength is critical, more resistant to mechanical damage but prone to chemical corrosion.

What is the Difference Between STA Cable and SWA Cable?cid=14

Ⅲ. Different Usages

● STA CABLE USAGE

▶Underground Installations: suitable for low voltage(0.6/1kV) power distribution where moderate mechanical protection is needed, such as in underground ducts or direct burial with light to moderate soil pressure.

▶Indoor/Industrial Applications: Used in fixed installations like control panels, motor connections, and sub-distribution boards where steel tape armor provides crush resistance without excessive weight.

▶Marine Environments: Offering protection against moisture and moderate mechanical stress.

● SWA CABLE USAGE

▶High-Stress Environments: ideal for medium voltage (1-35kV) applications requiring tensile strength,such as overhead lines, direct burial in rocky soil, or areas prone to rodent damage.

▶Industrial &Utility Projects: Used in substations, mining, and construction sites where steel wire armor resists bending and pulling forces during installation.

▶Long-Distance Transmission: preferred for underground or overhead transmission lines due to its superior mechanical durability.

What is the Difference Between STA Cable and SWA Cable?cid=14

Ⅳ. Different Weights

STA Cables have fewer steel tapes, so they're lighter.

SWA Cables have more steel wires, so they weigh more.

Conclusion

	STA Cable	SWA Cable
Armor type	Steel tape offers moderate crush resistance but less tensile strength	Steel wire armor provides superior tensile strength but may corrode faster in corrosive environments
Voltage	Low voltage (≤1kV)	Medium Voltage (1kV-35kV)
Environmental Stress	Vulnerable to moisture and UV exposure	More resistant to mechanical damage but prone to chemical corrosion
Installation	Fixed, underground ducts	Direct burial, overhead, harsh terrain
Weight	light weight	high weight