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This is Why Wires Have Two Parts

Wires are cylindrical pieces of metal that are flexible and can vary in size (millimeters to centimeters). The most common size for residential wiring has a diameter of 0.75 inches (19 mm). These wires carry current from an electrical source to lights, equipment, or appliances that may need power. Wires have two parts: conductors and insulators. Conductors are materials that are known for their low opposition to electrical flow. Insulators are known for their excellent capability to stop the flow of current.

It might look like a simple concept, but every wire needs some level of protection against over-currents. Wires have two parts for safety purposes and to convey electrical flows through these cylindrical pieces of metal.

Wires consist of a conductor, which channels the electrical flow, and insulation, which blocks the flow of electricity. It prevents an electrical overload (too much current) or under-currents (not enough current). They can incorporate other auxiliary elements that guarantee their longevity and ability to carry power over long distances. For successful wiring and electricity usage, both conductors and insulators have to work together to get clean and safe energy where needed.

An Overview of Wires

A wire is a long narrow piece of metal used to join things or carry electric current. Electrical wires supply, transform, transfer and distribute electrical energy. The wire is a single electrical conductor, whereas a cable is a group of wires swathed in the sheathing.

Manufactures produce wires from copper, aluminum, or other non-ferrous metals. For a long time, technicians have preferred copper since it is the best conductor, but aluminum is gradually replacing it in most electrical applications due to its high price. Experts must use more strands to create a more extensive conductor to make aluminum as effective as copper.

Types of Electrical Wires

  • Solid-core wire comprises a single strand and usually has an insulating jacket. Technicians use solid-core cables for low voltage applications such as lamps, loudspeakers, or household appliances.
  • Stranded wire consists of several solid strands bundled together. Technicians use the stranded wire in high voltage and low current applications. It is flexible, more durable, and can be soldered easily.
  • Multicore wire has several cores insulated from each other by a plastic or rubber covering called insulation. You can use multicore cables for motors, generators, and control circuits where the currents vary with time.
  • Braided wire comes with several strands twisted together and insulated by a plastic or rubber covering. It has high strength and cannot bend easily. Experts use them in applications where they will not flex, such as power cords for tools

Size of Wires

The wire gauge determines the right size for a specific application.  The indicator determines the amount of current that the wire can handle. Technicians determine if the wire is the proper size and has an ampere rating equal to or superior to the item’s requirement.

The most common household wires are 14-gauge (0.75-inch diameter), 12-gauge (0.59 inch), and for smaller appliances, 18-gauge (0.32 inch). When concealing wiring is, use 22-gauge (0.33) or 24-gauge (0.25 inch), which are thin enough not to show through walls and can easily blend into the background.

Insulation of Wires

Insulation is a crucial non-conductive material that surrounds and protects the individual wires. Professionals insulate wires to resist electric current in electrical applications. The insulation prevents short-circuits and provides mechanical protection for cables. Manufacturers produce insulation with rubber, plastic, and fiberglass that can withstand high temperatures and moisture without degrading or deteriorating. The most crucial property of wire insulation is its ability to resist the flow of electric current by blocking it.

Parts of a Wire

There are two parts of wire

  • Conductor. A conductor is a material (usually a metal such as copper) that allows electrical current to pass quickly. Electrons make the current. You cannot see these particles, but they are always in movement. They flow from high to low potential, i.e., from the battery to the light bulb. Most frequently specified for types of conductors are copper, aluminum, copper-covered, and high strength copper alloys. Not all conductive metals have the same level of conductivity- copper is the best conductor.
  • Insulator. An insulator prevents electricity from flowing through it by blocking or slowing down electrons. The insulation materials such as plastic, rubber, polyethylene, asbestos, thermoplastic, or varnished cambric materials have impaired electron mobility. Insulators provide a barrier between the conductors and keep them electrically separated.

Why Does a Wire Have two Parts?

The most crucial reason why wires have two parts is to protect people from electrical shock and prevent fires. When electricity travels through a material, it ends up losing energy which generates heat in the process. The insulation prevents this loss of power by not allowing the current to travel between two points close to each other. This way, there will be no short circuit or fire if something goes wrong with the system. Electricity is a dangerous form of energy, and it can kill.

Electrons flowing through a conductor or wire tend to generate heat from their high-speed motion and the energy they need to move electrons from their valance shell to new atoms, creating a current flow. The heat can build up, and if surrounded by flammable materials such as wood, paper, and sheetrock, it can ignite and cause a fire. Insulation helps dissipate the heat as well as prevent the wire from getting too hot.

It’s also important to know if you deal with DC or AC power in a given wire. AC power is the standard form of electrical energy used in homes and businesses. The voltage is continually changing as it alternates from positive to negative, so AC power can’t provide a constant supply of electricity.

DC stands for the direct current, which means that electrons move forward continuously through an entire wire without reversing direction- this ensures steady flow, which is vital for powering equipment such as motors.

In AC, power current likes to travel near the surface of a wire, causing a magnetic field to form around it. It helps to reduce the amount of heat generated.

In DC power, current travels through a wire in an unpredictable pattern and can cause more resistance than AC, generating more heat near the wire’s core (core heating). Experts use thicker copper cables to transmit large amounts of energy for heavy machinery and overhead lines.

Troubleshooting Wires

You can find defects in the wire by using an ohmmeter. Below are common faults that you can identify;

  • Broken wires, short circuits, and differences in resistance between conductors are the main faults. A broken wire will show two open ends on the meter, which means no current flows through it (an infinite reading). It can also tell that a fuse has blown or an electrical device has burnt out.
  • A short circuit will have low readings of ohms because both leads of the meter are connected. The resistance between conductors will show an infinity reading, which means no electrical flow through it (open circuit).

When troubleshooting wire, always check if the circuit has power before testing for any defects in the wiring or equipment to avoid electric shock and fire hazards. Always turn off power at the main switch before working and use a non-contact voltage detector to detect if the wires are still live.


Electricity can be dangerous, and that’s why wires have two parts. When electricity travels through a material, it ends up losing energy which generates heat in the process. The insulation prevents this loss of power by not allowing the current to travel between two points close to each other. This way, there will be no short circuit or fire if something goes wrong with the system and prevent people from electrical shock and fires


Jordan Harris

From the earliest age I can remember, I was planning and building things, and there was no question that Architecture was the right career fit for me. With more than 20 years of experience in the industry, I am absolutely thrilled and privileged to share my knowledge and experience with everyone through this blog.

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