If you’re planning an electrical project, it’s important to understand the different types of electrical wiring and their uses. From mains power cables to specialized wiring used for specific tasks, this guide explains some of the most common varieties available and what they are used for. This will help you make the right choices for your project.
However, you should always remember that electrical work can be dangerous and should only be done by a qualified professional. At M.R. Electricians, our team of experienced and certified electricians is here to help you with all your wiring needs. Don’t hesitate to get in touch for more information.
NM Cable
Nonmetallic (NM) cable is commonly known by the name Romex and is the most widely used type of residential wiring. It is a flexible cable made up of two or more separate wires, which are encased in a plastic outer jacket. NM cable typically has one or several hot (black or red) wires, a neutral (white) wire, and a ground wire. It is made for indoor use preferably in dry areas. The most frequently found sizes along with their amperage (amp) ratings are14-gauge (15-amp circuits)12-gauge, (20-amp circuits)10-gauge, (30-amp circuits)8-gauge, and (40-amp circuits)6-gauge (50-amp circuits).
THHN/THWN
THHN and THWN are named according to their properties. THHN stands for
- T: Thermoplastic
- HH: Highly heat-resistant
- and N: Nylon-coated.
THWN on its part stands for
- T: Thermoplastic
- H: Heat-resistant
- W: Waterproof
- and N: Nylon-coated.
These circuit wires are different from NM cables in that they are single conductors each having its own insulation. On the other hand, an NM cable has several insulated conductors housed in a plastic sheathing. They are the two most frequently used types of insulated wire inside the conduit and should not be handled when the circuit is turned on. They are mostly applied in uncompleted areas like garages, basements, and attics.
UF Cable
Underground feeder or UF cable is a type of NM cable that is designed to be used underground and in wet locations. It is made with a thicker jacket and has water-resistant insulation that helps in preventing it from being damaged by moisture. UF cables can also be buried directly in the ground without a conduit since they are designed for direct burial applications. They have insulated hot and neutral wires along with a bare ground wire. Unlike NM cables, UF cables have a sheathing around each wire and an outer sheathing around all of the wires. It is mostly used for major circuit wiring and connecting outdoor fixtures.
Low-Voltage Wire
Low-voltage wiring refers to a variety of cable, wire, and related products that are designed specifically for use in low-voltage circuits that require no more than 50 volts. This type of wiring is usually used for telecommunications, security systems, alarms, landscape lighting, and thermostats. The low-voltage wire is not capable of carrying the same amount of electricity as regular NM or THHN cables and is typically used for powering small appliances or fixtures. It is generally smaller and cheaper than other standard circuit wires.
Phone And Data Wire
Made from copper, telephone, and data wiring are low-voltage wires used to connect home or office telecom systems. The wiring is used to install phone lines, computer network cables, and other low-voltage devices. It generally consists of four to eight wires. The most common type is Cat (category) 5 which houses eight wires held together in four pairs. It is also cheaper than other types of wires like UF or NM cables. Data wiring can carry a low level of voltage, usually less than 30 volts – which is considered safe (in comparison to the 120 volts typically found in residential circuits). Nonetheless, there’s always potential for data wires to come into contact with household wiring and it should be handled carefully. So, when dealing with bare wires err on the side of caution and keep your distance!
Armored Cable
Armored cable (AC) wiring, also known as BX cabling, has been around since the early 1900s. It is designed with a flexible metal exterior that provides an extra layer of protection for its interior conductors. When it comes to home electrical wiring, local regulations can be more rigid than federal standards. This can mean that in certain areas NM cables cannot be used due to this restriction, and instead armored or AC cables must be employed. This cable type is very rarely used anymore. This has been replaced in most instances by Metal Clad (MC) Cable. This cable, unlike AC cable has an insulated ground conductor, while AC cable uses a bonding wire to enable the steel jacket act as a ground path.
How to Choose The Right Electrical Wiring
Choosing the right type of wiring for your project can become complicated. It is always important to be aware of any local regulations and codes before beginning a wiring project. If you need help determining what kind of wiring would work best, contact a local contractor or electrician who can provide advice and professional installation services. With the right kind of wiring installed correctly, your electrical appliances and devices will work safely and efficiently.
Ultimately, the type of wiring you choose should be based on the function it needs to serve, its location, and any regulations that apply. For instance, UF wire is preferable for outdoor projects or in wet locations, while low-voltage wires are better suited for telecommunications and alarm systems. Likewise, MC wiring must be employed in certain areas due to local regulations. With careful consideration of all these factors, you can make an informed decision about the best type of electrical wiring for your project.
M.R. Electricians is Only a Call Away
While this guide is meant to give you a basic understanding of the different types of wiring and their uses, it is still best to contact a professional electrician for any major electrical projects. The experienced and licensed technicians at M.R. Electricians have provided quality service across the Rockville, MD & Pinellas Country, FL area for over 25 years. Whether you’re looking to install new wiring or update existing ones, our team of professionals can help. Contact us today at (301) 871-0477 for an estimate!
