How to Choose the Right Armoured Cable for Your Project
Armoured cable is one of the most durable and reliable electrical cable types available, making it ideal for installations where additional mechanical protection is required. Whether you're supplying power to an outbuilding, running cables underground, or installing industrial equipment, selecting the correct armoured cable is essential for safety, performance, and long-term reliability.
This armoured cable buying guide explains what armoured cable is, its common uses, available sizes, and the key factors to consider before purchasing.
What is Armoured Cable?
Armoured cable, commonly known as Steel Wire Armoured (SWA) Cable, is a power cable designed with an additional layer of steel wire protection between the inner cable cores and the outer sheath.
The steel wire armour provides:
- Mechanical protection against impact and damage
- Protection from accidental digging or external forces
- Increased durability in demanding environments
- Additional earthing capability in some installations
SWA cable is widely used across domestic, commercial, agricultural, and industrial applications where standard cable may be vulnerable to damage.
Common Uses for Armoured Cable
Armoured cable is frequently used for:
- Powering garages and workshops
- Garden buildings and sheds
- Outdoor lighting installations
- Electric vehicle (EV) charging points
- Agricultural buildings
- Commercial premises
- Industrial machinery
- Underground power supplies
- Solar installations
- External power distribution systems
Its robust construction makes it particularly suitable for outdoor and underground installations.
Types of Armoured Cable
2 Core Armoured Cable
Typically used where an earth conductor is not required within the cable itself or where armour is used as the earth path.
Common applications include:
- Outdoor lighting
- Certain single-phase power supplies
- External equipment installations
3 Core Armoured Cable
Includes live, neutral, and earth conductors.
Commonly used for:
- Single-phase electrical supplies
- Garages and outbuildings
- Workshops
- EV chargers
- Domestic power installations
4 Core Armoured Cable
Often used for:
- Three-phase systems with neutral
- Commercial installations
- Industrial applications
5 Core Armoured Cable
Suitable for:
- Three-phase systems with neutral and earth
- Control equipment
- Industrial machinery
Choosing the Correct Armoured Cable Size
Selecting the right cable size depends on several factors.
Electrical Load
The cable must be capable of carrying the required current safely without overheating.
Higher-power equipment generally requires larger cable sizes.
Cable Length
Longer cable runs result in voltage drop.
As the cable length increases, a larger conductor size may be needed to maintain performance.
Installation Method
Armoured cable can be installed:
- Directly buried underground
- Clipped directly to surfaces
- Installed in ducting
- Mounted on cable trays
Installation methods can affect cable capacity and sizing requirements.
Environmental Conditions
Consider:
- Exposure to weather
- Ground conditions
- Temperature
- Risk of physical damage
- Presence of chemicals or oils
Future Expansion
If additional load may be added later, choosing a larger cable size now can save costly upgrades in the future.
Popular Armoured Cable Sizes
1.5mm² SWA Cable
Commonly used for:
- Outdoor lighting
- Small power supplies
- Garden installations
2.5mm² SWA Cable
Suitable for:
- Small outbuildings
- Garden offices
- Lighting and socket circuits
4.0mm² SWA Cable
Frequently used for:
- Workshops
- Garages
- Moderate power demands
6.0mm² SWA Cable
Common applications include:
- Garage consumer units
- EV chargers
- Larger outbuildings
10.0mm² SWA Cable
Typically used for:
- High-load circuits
- Large workshops
- Commercial power supplies
16.0mm² and Above
Suitable for:
- Industrial installations
- Three-phase systems
- Heavy-duty power distribution
Underground Armoured Cable Installation
Armoured cable is commonly installed underground because of its excellent protection against damage.
When burying armoured cable:
- Use appropriate burial depths in accordance with local regulations.
- Install warning tape above the cable where required.
- Protect cable entries with suitable glands.
- Use appropriate earthing arrangements.
- Follow BS 7671 wiring regulations.
Always consult a qualified electrician for installation advice.
Benefits of Steel Wire Armoured Cable
Excellent Mechanical Protection
The steel wire armour helps protect the cable from impacts, crushing, and accidental damage.
Suitable for Outdoor Use
The durable outer sheath resists moisture and weather exposure.
Direct Burial Capability
Many SWA cables can be installed underground without requiring additional conduit.
Long Service Life
Armoured cable is designed to provide reliable performance for many years.
Versatile Applications
Suitable for domestic, commercial, industrial, and agricultural installations.
Why Buy Armoured Cable from Wires Direct?
At Wires Direct, we supply quality armoured cable suitable for a wide range of electrical projects.
Benefits include:
- Cable cut to your required length
- Competitive UK pricing
- Fast nationwide delivery
- Trade and DIY friendly
- Wide range of SWA cable sizes
- Expert customer support
Whether you're wiring a garage, powering an outbuilding, or completing a large commercial installation, we have the armoured cable solution to meet your needs.
Frequently Asked Questions
What does SWA stand for?
SWA stands for Steel Wire Armoured, referring to the protective steel wire layer surrounding the cable cores.
Can armoured cable be buried directly underground?
Yes, SWA cable is commonly used for direct burial applications, provided it is installed correctly and in accordance with relevant regulations.
What size armoured cable do I need?
The correct size depends on current load, cable length, installation method, and voltage drop calculations.
Is armoured cable waterproof?
SWA cable is designed for outdoor use and offers excellent protection against moisture, although cable terminations must also be correctly sealed.
Can I buy armoured cable by the metre?
Yes. Wires Direct offers armoured cable cut to your required length, helping minimise waste and reduce project costs.
Expert Advice from Wires Direct
Choosing the right armoured cable is essential for ensuring a safe and reliable electrical installation. If you're unsure which SWA cable size or core configuration is suitable for your project, our team is here to help.
Browse our range of high-quality armoured cables today and find the ideal solution for domestic, commercial, agricultural, and industrial applications.