Is Romex the Same as NM-B Electrical Cable?
ROMEX® is a brand name by Southwire Company which is their very popular type of NM-B cable. Yes, Romex® is very similar to knock off brands of NM-B cable and the description of it would be Non-Metallic electrical cable.
Similar items in different industries would be “Kleenex” compared to a similar competitive brand of tissues or “Band-Aid” compared to a less popular type of adhesive bandage. Romex® has created quite the name for itself in the electrical field as the most popular and best version of NM-B cable.
Southwire’s Romex® comes in gauge sizes 14 through 2 each of which have either two or three conductors plus an additional bare copper ground wire. The 14 AWG cables are gray, the 12 AWG cables are yellow, the 10 AWG cables are oranges and the 8 through 2 AWG cables are black. The colors of the jackets allow for easy identification in homes and building when the installer is trying to quote a replacement cost for an owner.
The 14 AWG through 10 AWG NM-B cables are most commonly used in homes and building to run power from the electrical box to the lights, outlets and appliances throughout the home. Those three sizes depend on the amount of power in the home and how much power in particular will be driven to a specific spot. A dryer outlet will need more power than a standard plug outlet which requires a slightly larger wire to do so.
Remember that Romex® was engineered in a cost effective way as an indoor cable only. If it was able to run outdoors it wouldn’t be that cheap due to more engineering, testing, approving and material costs. If you need a cable to run outdoors you’ll need to see MC cable for outdoor and conduit use or UFB which is a direct burial underground feeder cable.
Speak to your electrician about the size of copper you need and then speak to your supplier of electrical wire about the conditions in which it will be placed in. Your supplier will help you understand the different types of insulation that protect copper wire from voltage, temperature, amperage and environmental conditions. The more protection the cable needs the more expensive it will most likely be.