The key difference between armoured and unarmoured cable lies in their level of protection. Armored cables include a metallic layer that adds durability in harsh environments, while unarmored cables lack this layer, making them lighter, more flexible, and cost-effective. This distinction forms the basis of the Armored vs. Unarmored Cable comparison.
What is an Armored Cable?
An armored cable is designed with an extra protective metallic layer around its insulated conductors. This armor provides mechanical strength, making the cable suitable for tough environments like underground installations or industrial setups.
Key features of Armored Cables:
- Strong mechanical and environmental protection
- Suitable for underground and outdoor use
- Can serve as an earthing conductor
- Resistant to rodent attacks and physical damage
Applications:
- Underground cabling systems
- Industrial plants
- Hazardous or outdoor areas
- High-voltage power transmission
What is an Unarmored Cable?
An unarmored cable does not have the metallic protective layer. Instead, it only comes with insulation and sometimes a non-metallic sheath. While they are not as durable, they are easy to handle and affordable.
Key features of Unarmored Cables:
- Lightweight and flexible
- Easier to install and maintain
- More cost-effective than armored cables
- Limited protection against external damage
Applications:
- Indoor electrical wiring
- Low-voltage and controlled environments
- Areas without mechanical stress
Armored vs. Unarmored Cables
Choosing between armored and unarmored cables often depends on the environment, required protection, and budget. Both types are designed for different purposes, and knowing their distinctions in construction, durability, applications, and cost helps in making the right choice.
Construction and Materials
Armored cables feature an extra protective layer wrapped around the insulated conductors. This layer is usually made from steel wire, aluminum tape, or sometimes non-metallic materials such as Kevlar, glass yarn, or fiber yarn. The armoring improves strength, resists corrosion, and allows the cable to withstand heavy stress and impact.
Unarmored cables, on the other hand, skip this additional layer. They consist of conductors with insulation and a simple outer sheath made of PVC, rubber, or other non-metallic material. While this design is easier to produce and install, it offers little protection against physical damage.
Protection Levels
The metallic armor in armored cables acts as a shield against crushing forces, abrasion, and even rodent bites. Many designs also resist moisture, and some include water-blocking compounds to keep the conductors dry.
Unarmored cables provide only basic insulation and are vulnerable to external damage. They are not suitable for direct burial or outdoor use where they may face harsh conditions.
Applications and Installation
Because of their strength, armored cables are used in industrial plants, outdoor projects, and underground systems. They perform well in rough terrains and are suitable for high-tension (HT) and low-tension (LT) power distribution. They are also useful in radio frequency (RF) setups, where the metallic layer can serve as extra shielding.
Unarmored cables are generally limited to indoor or low-risk environments, such as inside conduits, residential wiring, or building control systems. They are ideal for situations where mechanical protection is not a major concern.
Flexibility and Handling
The protective layer in armored cables makes them stiff and less flexible, requiring a wider bending radius during installation. This can make routing difficult in compact areas.
By contrast, unarmored cables are lightweight and highly flexible, making them much easier to handle in confined spaces. This is a major reason they are preferred in homes and small commercial setups.
Cost and Affordability
Because of the added materials and complex manufacturing, armored cables generally cost more—often about 15% higher than unarmored cables. Special versions, such as those with Kevlar, are even pricier and reserved for demanding applications.
Unarmored cables are budget-friendly and are commonly chosen for projects where extra protection is unnecessary.
Grounding and Electrical Continuity
In armored cables, the metallic layer can act as a natural grounding path, improving safety and reducing the need for a separate grounding wire. Some designs also include a thin ribbon for guaranteed electrical continuity, which is especially useful in RF applications.
With unarmored cables, a separate grounding conductor must be provided, which can slightly increase installation work.
Durability and Service Life
Armored cables are built for endurance. They can resist crushing forces, survive underground burial, and even deter rodent damage, giving them a long service life.
Unarmored cables are less durable and only reliable in well-protected environments, such as within walls or conduits.
Voltage Rating
Both armored and unarmored cables can be designed for high voltages, with some supporting up to 30kV. However, armored cables are better suited for challenging environments where both voltage capacity and physical protection are required.
Practical Selection Tips
When deciding between armored vs. unarmored cables, the environment should guide your choice:
- Use armored cables in outdoor, underground, or industrial settings where cables face stress, moisture, or potential damage.
- Opt for unarmored cables in indoor, protected areas where cost-effectiveness and flexibility are more important than strength.
Always check local electrical codes and consult a qualified professional before installation.
Comparision Table: Armored vs. Unarmored Cable
Here is a clear comparison table showing the difference between armoured and unarmoured cable:
| Feature | Armored Cable | Unarmored Cable |
| Protection | Metallic armor provides protection | No metallic armor |
| Durability | Highly durable, withstands harsh conditions | Less durable, for safe environments |
| Flexibility | Rigid due to armor | More flexible and bendable |
| Cost | More expensive | More affordable |
| Applications | Outdoor, underground, industrial | Indoor, low-risk areas |
| Earthing | Can act as an earthing conductor | Cannot be used for earthing |
Choosing Between Armored and Unarmored Cable
The choice between Armored vs. Unarmored Cable depends on your installation site. For outdoor, underground, or high-risk environments, armored cables ensure safety and reliability. For indoor or low-risk applications, unarmored cables are a budget-friendly solution.
Conclusion
In summary, the difference between armoured and unarmoured cable is straightforward: armored cables are tougher with metallic protection, while unarmored cables are lighter, flexible, and cost-effective. Choosing wisely in the Armored vs. Unarmored Cable debate ensures long-term performance, safety, and efficiency in electrical and communication systems.
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