Wire vs Cable: What Is The Difference?
Did You Know?
In the electrical industry, "wire" and "cable" are often used to indicate the same thing. However, there are major differences between wire and cable that should be considered for an electrical project to be successful.
The main difference between the two is that "wire" is always a single conductor, while the cable is a group of conductors insulated together in a single jacket. In each case, the conductors are usually made of copper, aluminum, or other conductive metal. A notable exception to this rule is a fiber optic cable made of optical fibers with no wires involved. Wires can be used independently or combined, depending on the particular installation. Nevertheless, the terms "wire" and "cable" are often interchangeably used in the industry, which, while not technically correct, is commonly understood.
What is a Wire?
An electrical wire is a thin thread of metal, typically made of copper or aluminum, used to carry electric current. It can have one or multiple strands but always acts as a single conductor. They can be used independently or as a component of a cable.
Two common types of wire are solid wire and stranded wire. Solid wires are single-stranded, whereas a stranded wire consists of multiple strands. Stranded electrical wires are more flexible, whereas solid wires are usually tougher. Electric wires can be bare or insulated with a protective sheath. They are commonly used to carry electricity and telecommunication signals in commercial and residential buildings. The benefit of using wires is that they are cheaper than cables, which can help one save energy costs and material and production costs. Electrical wires can be customized by combining individual wires as needed to meet the specific requirements of a project, which is also a plus. However, individual wires can be more difficult to install and manage than insulated and sheathed electrical cables.
Individual wires are often used in low-voltage installations and the internal wiring of appliances, but they can also be used in commercial and residential applications when codes allow it.
Wires are classified according to the gauge number and the electrical capability of the insulation.
Types of Electrical Wires
- THHN wire is a single-conductor wire used to construct residential and commercial buildings. It has PVC insulation and is resistant to heat, moisture, and chemicals. The wire is coated in nylon to protect against oil or gas exposure. It is typically installed within conduit or cable trays. Several THHN wires can be bundled together to form an outer jacket to form an NM-B cable.
- XHHW-2 is a building wire with XLPE insulation used in conduit.
- MTW wire is a flexible stranded copper wire with PVC insulation for machine tools.
- TFFN wire is a Thermoplastic Flexible Fixture Nylon wire for light fixtures and control circuits.
So, is THHN a wire or a cable? The answer is that it is a wire with one insulated conductor, just like XHHW, MTW, and TFFN. However, in practice, all of these can be referred to as "cable" when talking about them as products in the context of electrical installations. While it is not technically correct, everyone will understand what it means.
For accuracy and clarity, it's best to use "wire" when referring to single insulated conductors and "cable" when referring to multiple wires bundled together within a common sheath. Still, this rule is not followed all the time.
What is a Cable?
A cable is a thick cord that contains multiple wires or fibers insulated together. Just like wires, cables are also used to carry electrical signals. However, there is more variety to them. Some common cable types include multi conductor AC power cables, twisted pair cables, coaxial cables, and fiber optic cables.
Compared to wires, cables are well-protected and easily installed. However, cables come with a set number of conductors, which may not always match the specific requirements of a project. Therefore, paying attention to electrical project requirements is essential when choosing a cable. Electrical cables are used in data transmission, power transmission, and harsh environments where high-quality jackets and insulation are necessary.
Electrical cables have different mechanisms that suit their exact purpose. In coaxial cables, conductors are separated by an insulating layer to minimize signal degradation and interference. In thunderbolt cables, conductors carry power and multiple signals. In most cables, the conductors work together to carry the signal.
There is an immense variety of cables on the market for every imaginable purpose. Typical uses of cables include power and signal circuits in electronic devices; power transmission and lighting in buildings; long-distance undersea communication, etc.
Main cable classifications include gauge number, wire number, and jacket color. However, there could be more classifications. Electric cables can be classified based on:
- Insulation (thermoplastic, thermoset etc.)
- Conductor (copper, aluminum, etc.)
- Installation (underground, overhead)
- Voltage (low, medium, high)
