The machinery industry relies heavily on robust electrical systems to power critical equipment. However, harsh industrial environments pose significant challenges to the longevity and performance of electrical wiring.
Armoured cables provide a superior solution for protecting electrical conductors in demanding applications. In this blog post, we will explore the components and types of armoured cables, delve into their key advantages, and discuss their diverse applications across residential, commercial, industrial, and infrastructure sectors.
What Is Armoured Cable
Armoured cable, also known as armored cable or Type AC, is a type of electrical cable that features protective metal sheathing. This armored layer, typically made of interlocking metal tape or wire, is designed to provide an additional level of mechanical protection and durability compared to standard electrical cables.
The primary purpose of armoured cable is to safeguard the internal conductors and insulation from potential damage caused by external factors such as impact, abrasion, crushing, or environmental hazards. This enhanced protection makes armoured cable a preferred choice for installations where the cable may be exposed to harsh conditions or physical stresses.
Components of Armoured Cables
- Conductor: At the core of every armoured cable is the conductor – the pathway through which electrical current flows.
- Insulation: Surrounding each conductor is a layer of insulation, which provides electrical isolation between conductors and from the outer layers.
- Bedding: The bedding layer, also known as the inner sheath, is applied over the insulated conductors. It serves as a protective barrier, preventing the armor from damaging the insulation during installation and operation.
- Armor Layer: The armor layer is the defining feature of armoured cables, providing mechanical strength and protection.
- Outer Sheath: Encasing the armor layer is the cable’s outer sheath.
Types of Armoured Cables
Steel Wire Armoured (SWA)
Steel Wire Armoured cables feature a layer of galvanized steel wires wrapped around the inner cable core. The steel wires provide robust mechanical protection against impacts, abrasion, and crushing forces. SWA cables are well-suited for applications requiring high tensile strength and resistance to mechanical stress, such as underground installations or areas with high risk of physical damage.
Aluminum Wire Armoured (AWA)
Aluminum Wire Armoured cables use aluminum wires instead of steel for the armour layer. Aluminum offers good mechanical protection while being lighter in weight compared to steel. This makes AWA cables easier to handle and install, especially for long cable runs or applications where weight is a concern. However, aluminum may not provide the same level of tensile strength as steel.
Steel Tape Armoured (STA)
Steel Tape Armoured cables employ a layer of steel tape, wrapped around the cable core in a helical pattern. The steel tape provides effective mechanical protection with a thinner armour layer compared to wire armoring. This results in a cable with a smaller overall diameter, making STA cables advantageous in applications with space constraints or where a compact cable design is required.
Advantages of Armoured Cable
- Enhanced Mechanical Protection: The armour layer provides superior protection against mechanical stresses such as impacts, abrasion, crushing, and rodent damage.
- Environmental Resistance: Armoured cables offer increased resistance to environmental factors such as moisture, chemicals, and extreme temperatures. The armour layer acts as an additional barrier, preventing damage to the inner cable components and ensuring reliable operation in challenging environments.
- Simplified Installation: Armoured cables often require less additional protection during installation compared to non-armoured cables. The built-in mechanical protection eliminates the need for separate conduits or extensive cable trays, simplifying the installation process and reducing overall installation costs.
- Anti-Interference Performance: The armour layer can provide electromagnetic shielding, reducing interference from external sources.
- Enhanced Tensile Strength: Armoured cables, especially those with steel wire armoring, offer high tensile strength. This allows for longer cable spans and reduces the need for additional support structures.
What is Armoured Cable Used For
Residential Applications
In residential settings, armoured cables are used for outdoor lighting installations, underground power distribution, or in areas where the cable may be exposed to mechanical damage, such as in driveways or beneath landscaping.
Commercial Applications
Commercial buildings employ armoured cables for power distribution, especially in high-traffic areas or where cables are routed through concrete slabs or underground. They are also used for outdoor lighting, signage, or in parking lots where cables may be subject to vehicular traffic.
Industrial Applications
Industrial environments often present harsh conditions that necessitate the use of armoured cables. They are used for power distribution in factories, chemical plants, oil and gas facilities, or mining operations. Armoured cables provide reliable power supply while withstanding exposure to chemicals, extreme temperatures, vibrations, or heavy machinery.
Infrastructure Applications
Armoured cables are extensively used in infrastructure projects such as highways, bridges, tunnels, or railways. They are employed for power distribution, control systems, or communication networks where cables are exposed to outdoor elements, mechanical stresses, or potential damage from construction activities.