Selecting the right armoured cable is essential for safety, efficiency, and long-term reliability. The wrong choice can lead to costly maintenance or power failures.
Each type—such as SWA (Steel Wire Armoured) or STA (Steel Tape Armoured)—suits different environments and performance needs. Understanding these differences helps ensure a safe and cost-effective installation.
With over 40 years of cable manufacturing experience, NAN CABLE understands how vital proper cable selection is to project success. In this guide, we’ll explain how to choose the right armoured cable by considering factors like voltage level, installation environment, load capacity, and compliance standards—helping you make the most reliable and cost-effective decision for your project.
Table of Contents
5 Major Factors to Consider:
Voltage & Current Rating
The voltage rating defines the maximum electrical potential a cable can safely handle. Selecting the right rating helps prevent insulation breakdown and ensures safe operation.
Low-voltage (0.6/1kV) cables are suitable for residential and light commercial projects, while medium-voltage (up to 35kV) options are used in industrial and utility systems. Always confirm that the cable’s voltage and current rating match your system’s design parameters.
Voltage drop also affects performance. A high voltage drop can reduce power efficiency and equipment output. Choosing a properly sized conductor minimizes this loss and improves reliability.
Installation Environment
The installation environment plays a key role in determining the type of armour and insulation required. Factors like moisture, temperature, mechanical stress, and chemical exposure must be carefully evaluated to ensure durability and safety.
For instance, SWA (Steel Wire Armoured) cables are ideal for underground or outdoor use due to their strong mechanical protection, while aluminium armoured types are better in corrosive or coastal environments. In industrial settings, cables must resist heat, oil, and abrasion.
| Environment Type | Recommended Armour / Cable Type | Key Considerations |
|---|---|---|
| Underground | SWA / STA Armoured Cable | Rodent protection，moisture resistance, compression strength |
| Outdoor | SWA or Aluminium Armoured | UV resistance, corrosion protection, waterproof |
| Industrial | SY / LSF Armoured Cable | Heat, oil, and chemical resistance, flame retardancy |
Mechanical Protection Requirement
Mechanical protection is crucial for cables installed in harsh or high-risk environments. Armoured cables prevent damage from impact, pressure, or rodents.
For direct burial or outdoor installations, Steel Wire Armoured (SWA) cables offer excellent resistance to crushing and external force. In indoor or tunnel applications, Steel Tape Armoured (STA) cables are more suitable, providing reliable protection with lighter weight.
| Installation Area | Recommended Cable Type | Key Protection Advantage |
|---|---|---|
| Direct Burial / Outdoor | SWA Armoured Cable | Strong impact and crush resistance |
| Indoor / Tunnel | STA Armoured Cable | Lightweight, stable for fixed systems |
Choosing the right armour ensures long-term safety and minimizes costly maintenance or replacement.
Cable Flexibility
Cable flexibility is crucial for both installation and long-term reliability. Furthermore, flexible armoured cables simplify routing in tight spaces. They also work well around corners or in complex layouts. This is particularly valuable in wet areas, tunnels, or industrial sites. In these locations, cables often face frequent movement or vibration.
Consequently, a flexible structure helps reduce mechanical stress. It also prevents insulation cracks during operation. For fixed installations, moderate flexibility ensures stable performance. However, higher flexibility is better near machinery or in high-vibration areas. This increased flexibility provides superior fatigue resistance and durability.
Therefore, always consult a qualified expert before choosing these cables. This ensures they meet all safety and installation requirements.
Standards & Compliance
Compliance with established standards is essential for safe, reliable and legally approved cable installations. For armoured cables, selecting products that adhere to international and regional standards mitigates risk, ensures quality and safeguards long-term performance.
Global and Regional Standards
The table below shows the differences in applicable standards for armored cables in selected major regions.
| Region | Applicable Standards | Scope / Purpose |
|---|---|---|
| USA | NEC (National Electrical Code) | Guides cable installation, load sizing, voltage drop, separation of power and communication cables, and fire safety. |
| Australia & New Zealand | AS/NZS 5000.1 | Defines requirements for polymer-insulated armoured cables (up to 0.6/1 kV). |
| AS/NZS 3000 (“Wiring Rules”) | Governs wiring system selection, cable installation methods, and safety practices. | |
| Asia (various jurisdictions) | IEC 60183 | Selection of high-voltage cables. |
| IEC 60287 | Calculation of cable current ratings for safe operation. |
Why This Matters
Guided by recognized standards such as AS/NZS 5000.1 and IEC, engineers and project planners can confidently select armoured cables that meet project needs. These standards help ensure the construction, insulation, armouring, testing, and performance of each cable follow strict safety and installation requirements.
Local Compliance & Certification
Projects in different countries often include additional regional regulations—such as fire resistance, environmental ageing, or certification by bodies like Underwriters Laboratories (UL). Neglecting local standards may lead to regulatory non-compliance, higher maintenance costs, or installation delays.
Common Mistakes in Armoured Cable Selection (and How to Avoid Them)
Even experienced engineers can make mistakes when choosing armoured cables. Let’s explore five common errors and how to avoid them.
Underestimating Electrical Load
Choosing a cable with low current capacity is a common mistake. It can cause overheating, failure, and even fire hazards. Always calculate your system’s total load, including startup surges from motors or compressors. Oversizing slightly provides a safe buffer for peak demands.
💡 Tip: Use reliable cable sizing software or charts to confirm the current-carrying capacity before ordering.
Ignoring Voltage Drop
Voltage drop increases with longer runs and higher currents. If ignored, equipment may malfunction or operate inefficiently. To reduce losses, use larger conductors or shorten cable runs. Always keep voltage drop within recommended limits—typically 3% for branch circuits.
Note: Copper cables have lower resistance than aluminum, making them ideal for minimizing voltage loss.
Overlooking Environmental Conditions
Temperature, moisture, and mechanical stress all affect cable performance. Ignoring these factors leads to faster wear and failure.
For example, high heat lowers current capacity, while underground setups demand moisture-resistant designs. Choose insulation and armor types that suit your environment—PVC for moisture, SWA for impact protection.
Misusing Charts and Calculations
Incorrect charts or misinterpreted data can result in serious selection errors. Each chart assumes specific conditions like temperature or grouping. Always verify your references against manufacturer data or IEC standards. When in doubt, consult an expert to confirm your sizing and voltage calculations.
Ignoring Bending Radius Limits
Bending the cable too tightly can damage insulation or armor. This mistake often occurs during installation. Follow the manufacturer’s recommended bending radius—usually several times the cable diameter. Using cable rollers or guides helps maintain the correct curve.
By avoiding these mistakes, you’ll extend cable life, boost system efficiency, and maintain compliance with international safety standards.
Armoured Cable Installation Tips
Proper installation ensures armoured cables deliver safe and long-lasting performance. Even durable cables can fail without correct handling. Follow these essential tips for a reliable setup.
Handle with Care
Avoid excessive bending or twisting during installation. Mishandling can damage the armour or insulation, reducing cable lifespan.
Use the Right Tools
Use professional cutters and strippers designed for armoured cables. The right tools prevent damage to the inner conductors and armour layer.
Fit Correct Glands
Select the proper gland type and size for your cable. Tighten it securely to ensure grounding and maintain a moisture-resistant seal.
Protect Underground Installations
When installing cables underground, place them in suitable ducts or conduits. Add warning markers to prevent future excavation damage.
Follow Standards and Safety Rules
Always comply with local and international standards such as IEC 60502 or AS/NZS 5000.1. Before installation, disconnect power and wear proper safety gear.
Pro Tip: Regularly inspect installed cables for wear or corrosion. Early maintenance helps prevent costly repairs and power failures.
NAN CABLE-Partner with Experts for Reliable Solutions
Choosing the right armoured cable is vital for safety, performance, and long-term reliability. By understanding key factors, following proper installation practices, and avoiding common mistakes, you can ensure every project runs smoothly and efficiently.
At NAN CABLE, we manufacture armoured cables in full compliance with international standards such as IEC and AS/NZS. Our technical team can also customize specifications, testing, and documentation to meet your exact project requirements.
Contact NAN CABLE today to discuss your needs and get expert support for safe, compliant, and cost-effective cable solutions.
