When people search for MC cable, they are often looking for a cable that can protect conductors without requiring a separate conduit system. That makes sense. In commercial, industrial, utility, and equipment wiring applications, labor time, mechanical protection, grounding, and installation method all matter. But there is a little confusion around the terms.
MC cable and interlocked armored cable are closely related. In many cases, MC cable uses interlocked armor as part of its construction. So the real question is not always “MC cable or interlocked armored cable?” It is often “What type of armored cable do I need for this application?”
The answer depends on the circuit, voltage, environment, grounding needs, jacket requirements, and project specification.
What Is MC Cable?
MC cable stands for metal-clad cable. It is a factory-assembled cable that includes insulated conductors protected by a metallic covering.
In many commercial and industrial applications, MC cable is used as an efficient alternative to installing individual wires inside conduit. Instead of pulling separate conductors through a raceway, contractors can use a cable assembly that already includes the conductors and protective metal covering.
MC cable may be used for service circuits, branch circuits, feeder circuits, power wiring, control wiring, and equipment connections, depending on the cable construction and installation requirements.
One reason MC cable is popular is that it can save time. The armored construction helps protect the conductors while giving installers a more flexible wiring method than rigid conduit in many applications.
What Is Interlocked Armored Cable?
Interlocked armored cable is cable with a protective metal armor layer formed around the cable core. The armor is made with a continuous metal strip that is wrapped and interlocked to create a flexible protective covering.
This armor helps protect the cable from mechanical damage. It also allows the cable to bend more easily than many rigid raceway systems.
Interlocked armor is used on many different cable types, including certain MC cable constructions, medium voltage cable, fire alarm cable, health care facilities cable, power cable, control cable, and industrial cable assemblies.
That is why “interlocked armored cable” is a broader construction description, while “MC cable” is a specific cable type or classification.
The Simple Difference
MC cable is a type of metal-clad cable. Interlocked armored cable describes a cable construction that uses interlocked metal armor for mechanical protection. In many situations, an MC cable may also be an interlocked armored cable. The terms overlap, but they do not mean exactly the same thing. A good way to think about it is this:
MC cable tells you more about the cable type and how it may be used in electrical installations. Interlocked armored cable tells you more about the physical protective armor around the cable.
For purchasing, quoting, and specification purposes, both details matter.
Why Interlocked Armor Is Used
Interlocked armor is used when the conductors need added mechanical protection. This may be important in commercial buildings, industrial plants, utility environments, equipment wiring, health care facilities, fire alarm systems, and medium voltage installations.
The armor can help protect the cable from impact, abrasion, crushing, and jobsite damage. It can also reduce the need for separate conduit in certain approved applications. That can be valuable when a project needs a balance of protection, flexibility, and installation efficiency.
For example, a commercial building project may use armored cable for branch circuits or feeders. An industrial facility may need armored cable for equipment or control circuits. A utility or infrastructure project may require armored medium voltage cable with a specific jacket, insulation, grounding, or shielding design.
Where MC Cable Is Commonly Used
MC cable is commonly used in commercial, industrial, institutional, and utility applications. It may be selected for branch circuits, feeder circuits, service circuits, lighting, power, control, and equipment wiring.
It can be helpful in projects where conduit installation would be more time-consuming or where a flexible armored cable assembly better fits the installation path.
MC cable is also used in some machine wiring and remodeling applications where conductors need physical protection and the cable needs to bend around building or equipment conditions.
The exact use depends on the cable rating, conductor type, grounding method, jacket, environment, and local installation requirements.
Where Interlocked Armored Cable Is Commonly Used
Interlocked armored cable is used anywhere added mechanical protection is needed and the cable construction is approved for the application.
Common uses include commercial wiring, industrial equipment, branch circuits, feeder circuits, fire alarm circuits, health care facilities wiring, utility applications, medium voltage power distribution, and control circuits.
Some interlocked armored cables are designed for 600V applications. Others are built for medium voltage power systems, such as 5kV, 8kV, or 15kV applications. Some may include shielding. Some may include grounding conductors. Some may include aluminum armor, galvanized steel armor, PVC jackets, CPE jackets, or other construction features.
That is why it is important to match the cable to the actual project specification.
MC Cable vs. Conduit and Wire
One reason MC cable is often specified is because it can be a practical alternative to conduit and wire. With conduit and wire, the raceway is installed first, and then individual conductors are pulled through it. With MC cable, the conductors and metal covering are part of one cable assembly. This can help reduce installation time in many projects. It can also simplify routing in certain areas where flexibility is useful.
That does not mean MC cable replaces conduit in every situation. Some installations still require conduit, and some project specifications may call for a different wiring method. The right choice depends on the code requirements, jobsite conditions, electrical design, and environment.
Shielded vs. Unshielded Armored Cable
Some armored cable is shielded. Some is unshielded. Shielded armored cable may be used when electrical stress control, signal protection, or interference management is important. This is especially common in certain medium voltage, power, control, instrumentation, or industrial applications. Unshielded armored cable may be suitable when shielding is not required by the system design or project specification. The choice depends on voltage, circuit type, equipment, installation environment, and electrical requirements.
If a project calls for medium voltage Type MC cable, for example, shielding may be part of the specification. If the project calls for a 600V branch circuit cable, the construction may be different.
Aluminum Armor vs. Galvanized Steel Armor
Interlocked armored cable may be available with different armor materials, including aluminum armor and galvanized steel armor.
Aluminum armor is often selected when lower weight and flexibility are important. Galvanized steel armor may be used when additional mechanical durability or project-specific construction is required.
The armor material is only one part of the cable decision. Buyers also need to consider the conductor material, conductor size, insulation, jacket, voltage rating, grounding, shielding, temperature rating, and installation environment.
How to Choose the Right Cable
The best way to choose between MC cable options or other interlocked armored cable constructions is to start with the project requirements.
First, identify the circuit type. Is it service, branch, feeder, power, control, fire alarm, health care, or medium voltage? Then confirm the voltage rating, conductor count, conductor size, grounding needs, insulation type, jacket material, armor material, shielding requirement, and installation environment.
It also helps to know whether the cable will be installed indoors, outdoors, in a tray, in a raceway, in a wet location, in an exposed area, or in a space where added mechanical protection is especially important.
A request for “MC cable” may not be specific enough. A request for 600V Type MC cable with copper conductors and grounding, or 5kV shielded Type MC cable with interlocked armor and a PVC jacket, gives a supplier much more information to work with.
Why the Terms Matter When Requesting a Quote
Using the right terminology helps avoid quoting delays and product mismatches. If you need MC cable, say so. If the project specification calls for interlocked armor, include that detail too. If the cable needs to be shielded, jacketed, rated for a specific voltage, or built with aluminum or galvanized steel armor, those details should be included in the request. The more complete the information, the easier it is to match the cable to the project.
Custom Cable Corp. supplies interlocked armored cable for commercial, industrial, utility, health care, fire alarm, and medium voltage applications where added mechanical protection is required. Available options may include Type MC, armored fire alarm cable, health care facilities cable, XHHW-2, EPR, XLP, shielded, unshielded, aluminum armor, galvanized armor, copper conductor, grounding conductor, 600V, 5kV, 8kV, and 15kV armored cable options.
FAQs About MC Cable and Interlocked Armored Cable
MC cable is a type of armored cable, but not every armored cable is MC cable. MC cable refers to metal-clad cable, while armored cable is a broader term for cable with a protective metal covering. Some armored cables are designed for different applications, voltage ratings, circuit types, or installation environments.
To quote MC cable, provide the voltage rating, conductor material, conductor size, number of conductors, grounding requirement, armor type, jacket requirement, length, and application. It also helps to include whether the cable is for service, feeder, branch circuit, control, fire alarm, health care, or medium voltage use.
Some interlocked armored cable can be used outdoors, but only when the specific cable construction is rated for that environment. Outdoor use may require the proper jacket material, sunlight resistance, moisture resistance, wet-location rating, and approved fittings. Always match the cable to the project specification and installation conditions.
Jacketed MC cable includes an outer jacket over the metal armor. The jacket can provide additional protection against moisture, sunlight, chemicals, abrasion, or environmental exposure depending on the material and rating. Jacketed constructions are often used when the cable needs more protection than bare armor alone provides.
A project may require armored cable when the conductors need added protection from physical damage, when installation efficiency is important, or when the specification calls for a cable assembly that can reduce the need for separate conduit. Armored cable is often used in commercial, industrial, utility, equipment, health care, fire alarm, and medium voltage applications.
