What is the difference between Romex and THHN wire?
“Romex" is a product with multiple insulated and often uninsulated wires in one jacket so you only have one thing to route and it protects the insulation on the conductors. If there is a uninsulated wire present it is used as a safety ground. THHN is a single insulated conductor usually what I have used has a two level insulation.
What kind of cable is Romex?
- NM wire can be installed in plastic boxes and does not require the extra step of grounding the box itself.
- NM wire is lighter than metallic sheathed wiring, so it is easier to handle.
- NM wire is easier to unspool and straighten out because the PVC sheathing is pliable.
- It is easier to pull through holes in studs because of the smooth sheathing. ...
Does all Romex have a ground wire?
To understand the issue with ungrounded romex, we first need to understand what the ground wire does? (Note that the name ungrounded romex implies it has no ground) The ground wire is there for personal safety, it’s that simple.
Can Romex wire be used as SOOW cable?
NM-B (Inside) “Romex” Commonly referred to as “Romex” cable, this type of electrical wire (Non-Metallic Sheathed Cable) may be used for both exposed and concealed work in normally dry locations at temperatures not to exceed 90°C (with ampacity limited to that for 60°C conductors), as specified in by the National Electric Code (NEC).
What is a Romex used for?
Romex® cables typically consist of multiple THHN wires bundled together and sheathed in polyvinyl chloride (PVC), making them suitable for indoor applications such as garages, interior walls and surface wiring above ground. Contractors often use these wires to connect electrical panels to appliances and lights.
When would you use Romex cable?
Romex is used for most lighting and outlet circuits in your home. Romex will be labeled with "12-2" or "12-3". The first number indicates the gauge of the wire. You choices are typically 10, 12, or 14 gauge.
What is the difference between Romex and NM wire?
NM wire is easier to unspool and straighten out because the PVC sheathing is pliable. It is easier to pull through holes in studs because of the smooth sheathing. In the case of Romex, a coating is added that makes the sheathing more slippery. NM cable is easier to cut with just a set of side-cutting pliers.
What type wire is in Romex?
Romex wire is made out of two or three THHN wires combined with a grounding bare copper wire. Like the THHN wires, Romex wire can't be used outside because of its minimal PVC jacket protection.
Is Romex wire illegal?
While allowed in houses, it is important to note that the NEC prohibits the use of Romex conductors in residences higher than 3 stories, while the wires are prohibited altogether in commercial buildings.
Which cable is best for house wiring?
Best Companies Wire is best for House WiringSr. No.Best Company Wire for home Wiring1.Havel's India Limited2.Polycab Wires3.Finolex Cables Limited4.Syska Wires6 more rows•Sep 13, 2021
Why does Romex have paper?
From what I can tell, the paper around the bare grounding conductor is simply a separator. Where as the paper wrapped around all the conductors, is there to hold the assembly together while the outer jacket is applied. with a bare copper ground wire wrapped in paper and laid parallel between the insulated conductors.
Is Romex wiring safe?
Romex wire is one of the better and safer alternatives for the following reasons: Presence of a ground wire. Sheathing is flame-resistant and heat resistant, able to withstand a temperature of 90 degrees Fahrenheit. Longer-lasting due to copper metal composition.
What are five common cable types used in residential wiring?
NM Cable. The most common type of home electrical wiring is the NM cable, also known as the Romex cable, after the most popular electrical wiring brand name. ... Armored Cable. ... Underground Feeder Cable. ... Low-Voltage Wire. ... THHN/THWN Wire. ... Phone and Data Wire.
What are the 3 types of wires?
Three types of wire used are :live wire ( Red colour)neutral wire(Black colour)earth wire (Green colour)
What type of wire is used for outlets?
12-gauge wire is the minimum requirement for outlets on a 20-amp circuit. 12-gauge wire can be used for outlets on both 15 and 20-amp circuits. 14-gauge wire is unsafe to use for outlets on a 20-amp circuit. 14-gauge wire can only be used for outlets on a 15-amp circuit.
Is it legal to run Romex in conduit?
No, you can not run your Romex wiring in conduits. What you're looking at in the code book is referring to THHN and other wiring, that while insulated with a single coat is not insulated with a second covering and bound to 2 or 3 other wires.
What is the name of the cable that is Romex?
What Is Romex Brand Electrical Cable? Romex is the brand name of a non-metallic (NM) sheathed electrical cable made by Southwire Company, LLC of Carrollton, Georgia. Southwire notes that they "vigorously monitor and protect the use of the Romex brand.".
Where did the name Romex come from?
Origin of Romex Brand Wire. The Romex name comes from Rome Cable Corp. of Rome, New York, which originally produced the cable. The company was an industry leader until it filed for bankruptcy in 2003 and its factory was largely demolished in 2010.
What is the color of the PVC in NM cable?
Wire Insulation. Wires within the sheathing are insulated with color-coded PVC (polyvinyl chloride). The individual conductors normally have black, white, and red insulation. Also present within the NM cable is a copper grounding wire that is usually left uncoated and bare but sometimes is coated in green PVC.
Why is NM wire easier to unspool?
NM wire is easier to unspool and straighten out because the PVC sheathing is pliable. It is easier to pull through holes in studs because of the smooth sheathing. In the case of Romex, a coating is added that makes the sheathing more slippery. NM cable is easier to cut with just a set of side-cutting pliers.
Why is cable sheathing so tough?
The sheathing is extremely tough. This is necessary to withstand the stress inflicted on the sheathing when the cable is pulled through holes in studs. To make connections with devices, cable sheathing is ripped laterally with a metal device called a cable ripper.
What is NM wire?
The non-metallic (NM) designation refers to the outer sheathing that bundles individual wires together like a cable. This is in contrast to metallic sheathed cable or conduit wiring, in which the bundle of individual conductors is protected by some form of a metal coil or metal conduit. Typically, there are three parts to NM electrical cable: outer ...
What gauge wire is used for NM?
NM cable comes in many wire gauges, but most household circuits will use 12-gauge or 14-gauge wire, with either two or three conductors inside (plus the bare copper ground wire). For example, a cable labeled "14-2 with ground" will have two insulated conductors with 14- gauge wires plus a bare copper grounding wire.
What is Romex wire?
Romex® wire a brand of housewire or non-metallic wire is electrical wiring commonly found in homes. Generally you can make more money by stripping the wires to get to the copper. Housewire has two jackets covering the copper inside.
Why is it taking so long to strip copper wire?
Because there are two jackets of insulation surrounding a single or couple strands of copper wire, you are wasting your time. You will be taking longer to strip the copper than you will be making money on it.
Why do some electrical wires have the same color?
Some have the same coloring along with gauge and when that happens it is because some electricians want to be able to have a better idea when they are running wires which is which.
What is a Romex cable?
Romex® is an electrical cable suitable for various indoor wiring uses , primarily for small businesses and homes. This wide-reaching wire, which can be bought in many different sizes and configurations, features a distinctive jacket that allows it to be pulled easily through conduit.
What is the size of a Romex wire?
Romex® wire is available with two or three conductors and in sizes from 14 American Wire Gauge (AWG) to 2 AWG. Sizes are labeled with a slash to show the wire size and the conductor number. For example, 14/2 Romex® means all the wires are 14 AWG and there are two conductors.
What temperature is THHN wire?
High-heat resistance: THHN wires are rated for as high as 90 degrees Celsius, meaning they are appropriate for most building types. Nylon coating: A nylon jacket wraps around the wire, protecting it from cuts and abrasions as well as destructive agents such as chemicals, oil and water.
What is a THHN wire?
THHN is the industry’s most popular single conductor electrical wire type. The acronym means “thermoplastic high-heat nylon,” which refers to components and characteristics of the wire’s jacket and insulation. Its capabilities and features have made it one of the most popular construction wires, and it passes the majority of building codes.
What is a romex?
Romex® is a product from Southwire, a reputable cable and wire provider. The “NM-B” code refers to the wire’s nonmetallic (NM) sheath and primary use in branch (B) wiring. Romex® is also called SIMpull®, another Southerwire trademark that refers specifically to their jacketing, which makes pulling wire through conduit much easier. Many electricians and consumers also use the name “Romex®” generically to mean any wire that is NM-sheathed — similarly to how some people erroneously use “Kleenex” to mean any brand of facial tissue. However, you should only use the name Romex® to refer to Southwire’s cables with the Romex® brand name.
What does "Romex" mean?
Many electricians and consumers also use the name “Romex®” generically to mean any wire that is NM-sheathed — similarly to how some people erroneously use “Kleenex” to mean any brand of facial tissue. However, you should only use the name Romex® to refer to Southwire’s cables with the Romex® brand name.
Does THHN wire meet building codes?
Some other advantages of THHN wire include the following: It meets most building codes: If you use THHN wire for your project, it will likely meet code. However, never assume that your project will meet code — always get your project approved with your local building code department before beginning work.
What is 14/2 wire used for?
However, these wires come in larger sizes than the thinner THHN wires; 14/2 and 6/3 are used widely as electrical wire, despite the fact that it can’t be used in conduit at all. The primary use for this type of wire is to run more than one conductor at a time through a separate grounding wire. UFB wire is one of the most popular ...
What are the different types of electrical wires?
Three Types of Electrical Wire: THHN, UFB, and Romex Wire Revealed. There are many types of electrical wire available for consumers, however, it’s easy to get confused by the different types. The most common types of electrical wire are THHN, Romex, and UFB wire.
What is THHN wire?
THHN wire is covered with a PVC jacket and nylon coating. This wire is a bare one conductor copper wire and is often used indoors or in conduit. The most popular sizes for THHN wire are 12 and 4/0, though other sizes are available for nonstandard projects.
Can you use Romex wire outside?
Because of the ‘bare essential’ nature of this wire however, it isn’t recommended for outside use. Romex wire is made out of two or three THHN wires combined with a grounding bare copper wire. Like the THHN wires, Romex wire can’t be used outside because of its minimal PVC jacket protection.
What is a romex wire?
ROMEX® is a cable of two or more wires enclosed in a plastic or rubberized sheath. The most common types of ROMEX® are rated only for indoor use and come in 14 and 12 AWG wire sizes. The cable includes a bare ground wire wrapped in paper. NM 14-2 ROMEX® has a black insulated wire, a white insulated wire and a bare ground wire, all 14 gauge. The 14-3 ROMEX® adds a red insulated wire. NM 14-2 ROMEX® is the most common type of wire used for residential wiring.
What is the trade name for NM wire?
Approximately 90 percent of the homes in the United States are wired using nonmetallic (NM), sheathed cable, known and referred to by the trade name ROMEX® . Sheathed cable is convenient and easy to run.
What is the NEC?
The National Electric Code (NEC) is responsible for ensuring the safety of all new and existing electrical wiring work done in the United States. The numerous codes within the NEC specify how to wire with safety in mind. Municipalities across the country adopt the NEC into their own ordinances and make changes to suit specific needs. The NEC makes no claim that conduit is safer than ROMEX®.
What is flexible metal conduit?
Flexible metal conduit, or FMC, looks similar to the old BX cable that was once popular before NM sheathed cable came out. However, it is not sold with wires inside and they must be pulled through the conduit after the conduit is installed. FMC requires special connectors. It is often referred to by the trade name Greenfield.
Does conduit double the cost of an electrical installation?
Conduit will double the cost of an electrical installation. If Greenfield FMC must be used , the cost may even triple, because Greenfield and the necessary connectors are quite expensive compared to EMT. Greenfield is seldom used for this reason. ROMEX® is the most economical type of residential wiring, but it lacks the flexibility of conduit wiring.
Can you use any color wire with romex?
While ROMEX® is available in a number of sizes, the insulated wires are all white, black and red. Using conduit, it is possible to use any color wire and implement color coding schemes not possible with ROMEX®. With conduit, you can pull two yellow wires from a switch to a light fixture.
What is a romex cable?
Romex is an NM type of cable having non-metallic sheathing and is commonly used for residential wiring purposes. It's the cable you'll likely use to wire your house. Below are NEC regulations that apply to Romex: 1 Romex cables should be clamped, protected, and secured on junction boxes, fixtures, and device boxes. 2 The use of devices that might damage cables, including overdriven staples and bent nails, isn't permitted. 3 It would be best if you secured NMC and NM cables at maximum intervals of 4½ feet. It's also critical that they remain safe within 12-inches of panels and junction boxes. 4 Romex wiring is permanent wiring in houses and shouldn't be employed as extension cords and appliance wiring substitutes.
What is the outer sheathing on a Romex cable?
The outer sheathing for a Romex cable is a 30 mil-thick PVC jacket that protects and bundles individual wire conductors. The sheathing is very tough to offer maximum protection. It is beneficial to withstanding the stress impacted on the sheathing when you pull the cable through holes.
What is the difference between BX and Romex?
The main difference in BX and Romex is the outer protective covering. Otherwise modern BX and Romex both have a positive, neutral and ground wire. In BX, the ground wire has a plastic protective sheathing where in Romex the copper wire is bare.
Where does the name Romex come from?
Romex comes from “Rome Cable Corp. of Rome, New York,” which produced the cable for the first time. The company was among the leading producers of cables until 2003, when it filed for bankruptcy.
How to remove outer armor of BX cable?
You can use at least three known ways to remove the outer armor of a BX cable: manually with pliers, with a unique BX cutting tool, or with a hacksaw.
Can you use Romex wire outside?
There are certain cases where you can’t use a Romex wire, such as outdoor environments or where the cable is exposed above the foundation walls. The electrical codes require conduit installations in such instances.
Is Romex wire used for residential wiring?
Romex wiring is mainly employed in residential wiring, although it’s still possible to achieve the task using conduit or metallic sheathed cables. The wire comes with several benefits that make it the most prevalent wiring option for homeowners.
Overview
Terminology
- Romex® is the specific brand name for a non-metallic (NM) building wire made by Southwire. In other words, Romex® is technically just one brand of NM cable. However, the term Romex is often used generically (though inaccurately) to describe any type of NM cable, no matter which manufacturer made it.
Design
- The NM designation refers to the outer jacket of the cable, indicating that it is a non-metal material. This outer sheathing is a 30 mil-thick PVC jacket that serves to bundle the individual wire conductors together and protect them. This is in contrast to metallic sheathed cable or conduit wiring, in which the individual conductors are instead protected by some form of a metal coil or …
Components
- Despite the NM label, the individual electrical conductors within the cable are indeed metalnormally copper that is jacketed with color-coded PVC (polyvinyl chloride). The individual conductors normally have black, white, and red insulation. Also present within the NM cable is a bare copper grounding wire.
Variants
- NM cable comes in many wire gauges, but most household circuits will use 12-gauge or 14-gauge wire, with either two or three conductors inside (plus a bare copper ground wire). For example, a cable labeled \"14-2 with ground\" will have two insulated conductors with 14-gauge wire plus a bare copper grounding wire. This cable is used for 15-amp circuits. A cable labeled \"12-3 with g…
Advantages
- NM wiring is very common in residential wiring, but it is also possible to wire a home using metallic sheathed cable or conduit. NM wiring has many advantages that make it the most popular type of wiring, especially for homeowners: All factors considered DIY electricians will find their projects easier and cheaper to complete when using NM wiring. Remember, though, that th…
Name
- The Romex name derives from the Rome Cable Corp. of Rome, NY, which originally produced the cable. The company was founded in 1936 and filed for bankruptcy in 2003. Today, the Romex brand is owned by the Southwire company as a trademark. As the company mentions on its website, they \"vigorously monitor and protect the use of the Romex brand.\" In other words, the …