Romex Wire The Basics For Geting Started

House wiring cable or Romex cable is one of the most used cables today. It comes in a wide range of sizes and combinations. The importance of using this particular cable is undeniable, and this is why we have decided to educate you about it. We are going to cover the basics of Romex cables, and our information will help you in choosing the appropriate Romex cable for use.


Romex Wire The Basics For Geting Started

What is Romex? What is 12/2 or 14/3 Electrical Cable?

In most of the houses and businesses, the electrical system is wired through and insulated wire, namely Romex. This is a famous brand for wire cable which is widely recognized for producing fine electrical wire. Typically, Romex cable includes two or more insulated wires within a flexible plastic sheath. You can run them through walls or floors, attics and more. Moreover, the sheathed cables are identical, meaning that you can interchange them easily. You should know that the labeling for every electrical wire is always standardized regardless of which company manufacture them.

Also, you can use flexible sheath cable more often through holes in studs. However, this is not possible if you are using metallic sheathed cable. Besides, a flexible sheath cable is cheaper than any cable. This is another great feature of using it. When you are using a Romex cable, you will see a label – NM-B. This label indicates the sheathing cable is made of non-metallic cable. Other than Romex, most brands use this label – NMC. Keep in mind the NM designation demonstrates that it is made of metallic sheathed cable.

If you see a rating of 14/3, you should understand that the gauge of the wire is fourteen and it has three conductors. In that case, the above image shows a sheathed cable that has two twelve gauge wires along with a bare twelve gauge ground wire.

What are Conductors?


All cables have wires, and they are defined by the term ‘conductor.’ For instance – a Romex cable with three conductors will have three different wires within the cable. Every cable will be marked with separate color so that you can easily identify them. In the case of residential wiring, the wires include a bare copper wire along with paper sheathing for protection. They are also isolated from one and another to make sure everything is safe. However, these wires are used as a ground wire, and they are not known as a conductor because most of the residential wiring needs ground wires often.

What about Sizing?

As we stated earlier that the conductors within a cable could be of different sizes and shapes, the major reason for this variety is the smooth transition of current through the conductor. For instance – a circuit consisting of a single light bulb would carry less amount of current than a circuit with three light bulbs. The reason for this is the light bulb only takes 1/2 an amp. However, if the circuit includes 200 light bulbs, it will require 100 amps current. Also, there has to be a big conductor size for handling the heat as well. So, you should understand that the wiring sizing is critical for proper maintenance of the circuit board.

Remember that almost all types of a 120Vac household circuit will be efficient at using a 14 gauge wire. In that case, the bigger the conductor size is, the smaller the gauge number is.

In another case, if you need to a three wire cable for wiring up a general 2-way switch, you will require 1/2 an amp. This means the gauge number is 14 and the two conductors consist of a bare ground wire as well.

Bottom Line

The bottom line is some manufacturers would place a green insulation on the ground wires. And, it will be regarded as a conductor. Yeah! Most people will be confused by this fact, but do not overthink. Usually, the house circuits are of a general kind, and that’s what you need to know for proper maintenance!

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