In modern electrical engineering, every detail in cable design affects safety, performance, and installation efficiency. Among the most widely used power cables, MC (Metal Clad) Cable and AC (Armored Cable) often attract comparison. Professionals frequently ask - "Why is MC less than AC?"
The answer lies not only in size but in structure, material optimization, and application flexibility. This article will explain why MC cables are typically smaller and lighter than AC cables, and how this seemingly small difference can significantly impact electrical installations, cost efficiency, and modern engineering trends.
Understanding AC and MC Cables: Standards and Structure
Before analyzing the difference in size, it's important to understand how MC and AC cables are defined in international standards and how their internal structures differ.
| Feature | AC Cable (Armored Cable) | MC Cable (Metal Clad Cable) |
|---|---|---|
| Applicable Standard | NEC Article 320 | NEC Article 330 |
| Grounding Method | Uses metal armor as equipment grounding conductor | Includes a separate insulated grounding conductor |
| Outer Armor Material | Interlocked steel or aluminum | Interlocked aluminum or steel, or corrugated sheath |
| Moisture Resistance | Limited – suitable for dry locations | Suitable for dry, damp, and even outdoor or exposed areas |
| Applications | Residential and light commercial wiring | Commercial, industrial, and exposed installations |
| Flexibility | Moderate | Higher – easier to bend and install |
In essence, AC cables rely on their metal sheath for grounding, while MC cables include a dedicated grounding conductor. This key structural difference directly affects their physical design and size.
Why Is MC Cable "Less" Than AC Cable?
The phrase "MC is less than AC" refers to the smaller outer diameter, lighter weight, and greater flexibility of MC cables. There are three main reasons for this:
Structural Optimization
MC cables are engineered with a separate grounding wire rather than relying solely on the armor for grounding. This allows for thinner, lighter, and more flexible armor designs, reducing the overall diameter without compromising strength.
Material and Manufacturing Efficiency
Modern MC cables often use aluminum alloy armor with advanced interlock designs. This reduces weight while maintaining durability. The compact layering process results in a smaller cable body that still meets all mechanical and electrical protection requirements.
Performance and Heat Dissipation
MC cables have better heat dissipation and improved conductor spacing, allowing for higher ampacity in smaller diameters. This technical advantage means that engineers can select smaller cable sizes to achieve the same or better performance compared with AC cables.
Application Differences Between MC and AC Cables
Although AC and MC cables share similar functions, their application environments are distinctly different.
- AC Cable is mainly used in dry, indoor applications such as residential wiring, concealed walls, and non-hazardous areas.
- MC Cable, on the other hand, is designed for broader environments, including damp locations, outdoor installations, industrial facilities, and data centers.
In addition, MC cables are approved for direct burial or concrete embedment (when specified), while AC cables are not. This versatility makes MC cables a preferred choice for modern construction, energy-efficient buildings, and prefabricated modular systems.
The Industry Trend Behind "Smaller" MC Cables
The fact that MC cables are smaller than AC cables is not just a matter of dimension - it reflects a broader industry evolution:
- Space Efficiency: Modern buildings demand tighter installation spaces. MC cables' compact size allows for easier routing through conduits and trays.
- Sustainability: Lighter materials reduce transportation energy and environmental impact.
- Labor Savings: MC's flexibility means faster installation, reducing project timelines and costs.
- Adaptability: As building systems become more integrated (data, lighting, HVAC), MC cables provide a universal wiring solution adaptable to various applications.
This evolution represents the electrical industry's shift toward smarter, leaner, and more sustainable cable systems.
Why Choose Dongguan Greater Wire & Cable Co., Ltd.
At Dongguan Greater Wire & Cable Co., Ltd., we specialize in high-quality AC cables, manufactured under strict compliance with NEC, UL, and international standards. Our AC cable products are known for:
- Superior armor strength ensuring mechanical protection and long service life
- Consistent conductivity and insulation integrity for stable electrical performance
- Competitive pricing and fast delivery, suitable for both large infrastructure projects and small-scale installations
We provide comprehensive technical support for design, installation, and after-sales service. Whether you are planning a commercial facility or residential project, our expert engineering team will help you choose the right cable solution that meets your exact requirements.
📞 Contact Us Today:
- Dongguan Greater Wire & Cable Co., Ltd.
- Tel / WhatsApp / WeChat: +86 135 1078 4550 / +86 136 6257 9592
- Email: manager01@greaterwire.com
No matter the size of your project, we offer full-service support - from consultation to delivery. Let's power your success with reliable, efficient, and safe cable solutions.