Electrical Wire

Plastic Sheathing Electrical Wire is used Extensively in Home Electrical Wiring

By Mark J. Donovan




Plastic sheathing electrical wire is used extensively in home electrical wiring. Plastic sheathing electrical wire is frequently referred to as Romex cable or wire. Romex is actually a brand name for a particular manufacturer of plastic sheathing electrical wire. There are a number of alternative plastic sheathing electrical wire manufacturers, and brand names on the market today besides Romex.

Plastic sheathing electrical wire is also referred to as NM (as in Non-metallic outer sheathing wire). In addition to plastic sheathing electrical wire, metallic sheathed electrical wire can also be found in homes.

However, it is more difficult to work with as it is heavier and more difficult to pull through holes in walls studs. Consequently most homeowners, and electricians, prefer to work with Romex or plastic sheathing electrical wire.

Plastic sheathing electrical wire consists of 2 or 3 insulated conductor wires and a bare copper ground wire. The black and red insulated wires are typically used as hot wires, and the white wire is used as neutral.

When buying Romex electrical wire, you will see markings on the wire, or packaging, indicating 14-2 or 14-3, or 12-2 or 12-3 electrical wire. The first number stands for the wire gauge, or wire thickness. The 14 gauge wire is used for 15 Amp circuits and the 12 gauge wire is used for 20 Amp circuits. The second number corresponds to the number of insulated wires in the sheathing.

For example, the 14-2 wire has a black and white insulated wire along with a bare copper wire, whereas the 14-3 has a black, red and white wire, along with a bare copper wire. 14-3 or 12-3 electrical wire is frequently used in 3-way switch circuits.

When buying Romex electrical wire, you will see markings on the wire, or packaging, indicating 14-2 or 14-3, or 12-2 or 12-3 electrical wire. The first number stands for the wire gauge, or wire thickness. The 14 gauge wire is used for 15 Amp circuits and the 12 gauge wire is used for 20 Amp circuits. The second number corresponds to the number of insulated wires in the sheathing.

For example, the 14-2 wire has a black and white insulated wire along with a bare copper wire, whereas the 14-3 has a black, red and white wire, along with a bare copper wire. 14-3 or 12-3 electrical wire is frequently used in 3-way switch circuits.

To strip back the plastic sheathing from Romex electrical wire, you can use either a jack knife, utility knife or a sheathing slitter tool. With a sheathing slitter tool, you just run the plastic sheathing electrical wire through the middle of the tool, approximately 6 inches, squeeze the tool and pull.

A nice clean slit in the plastic sheathing is produced and you can then pull it back from the bundled insulated and copper wires and trim it off with a utility knife.

Romex electric wiring cable

You can then use a pair of wire strippers to remove the insulation around the ends of the hot and neutral insulated wires.

Finally, when wiring a home with plastic sheathing electrical wire, it is important to use the right wire with the right circuit breaker. For example, with 14-2 wire it is important to not use a circuit breaker rated higher than 15 Amps. And for 12-2 electrical wire, you should not use a circuit breaker rated higher than 20 Amps.

Warning: When working with electricity use extreme caution to avoid the risk of electrical shock. Make sure to first shut off power at the main circuit panel and then confirm all power to the electrical fixtures and boxes are off prior to beginning any electrical work.


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