Electrical Wire Type & Use Timeline
| Wire Type | Dates | Comments & More Information |
| Telegraph Wires | 1844 | First commercial telegraph wires, Iron c ... |
| Telephone Wires | 1876 | Early copper conductors, insulated, low- ... |
| Edison Solid Iron Tubing | 1885 - 1910 | Also: existing gas pipes converted to el ... |
| Gutta Percha insulation | 1885 | Insulation on smaller conductors |
Full Answer
How dangerous is old electrical wiring?
Old electrical wiring that has not been inspected by a qualified Level 2 Electrician and approved to be safe is extremely risky and dangerous. This is because older systems, such as VIR cables and black rubber cables, are more prone to be damaged and wear down as time passes.
What you should know about electrical wire types?
- White insulation: Typically considered neutral but can sometimes be used as a hot lead in certain situations, such as switch loops. ...
- Green insulation and bare copper: Ground wire.
- Black insulation: Hot wire for switches and outlets.
- Red insulation: Hot wire for switch legs and hardwired smoke detectors
What are the different types of electrical wiring?
TYPES OF ELECTRICAL WIRING There are following types of electrical wiring. 1. Cleat wiring or Temporary wiring 2. Wooden or Batten wiring 3. Casing and Capping 4. Conduit Wiring 5. Trunking Wiring 1 Cleat Wiring or Temporary Wiring AIR UNIVERSITY, PAF COMPLEX E-9, ISLAMABAD It is a temporary wiring used for function and construction work.
What are the basics of electrical wiring?
- Guiding principles. The NFPA 70: National Electrical Code has numerous prescriptive requirements regarding wiring methods.
- Standard conductor types: insulation. ...
- Conductor markings. ...
- Aluminum versus copper. ...
- Stranded versus solid conductors. ...
- Obsolete conductor types. ...
- Metallic conduit. ...
- Rigid PVC conduit. ...
What type of wiring was used in old homes?
The oldest type of wiring system found in homes is called knob-and-tube, named for the insulating knobs and tubes that are used to run the wiring along and through the house framing. Knob-and-tube wiring was run as individual wires—one black hot wire and one white neutral wire—throughout the home.
What type of wiring was used in 1950?
Knob-and-tube wiring was the wiring method of choice for homes until, and in many areas, through the 1950s. Knob and tube wiring was a two-wire system that was quick and easy to install. Two separate insulated conductors were installed, a hot wire and a neutral wire.
What type of electrical wiring was used in the 1960s?
aluminum wireIn North American residential construction, aluminum wire was used for wiring entire houses for a short time from the 1960s to the mid-1970s during a period of high copper prices. Electrical devices (outlets, switches, lighting, fans, etc.)
What type of wiring was used in 1940?
Knob & Tube wiring1880 – 1940 – Knob & Tube wiring was the first type of electrical wiring in homes. This type of wiring consisted of two single wires run parallel within wall or ceiling cavities.
How were houses wired in the 1940s?
Knob and Tube wiring was an early standardized method of electrical wiring in buildings, in common use in North America from about 1880 to the 1940s. The system is considered obsolete and can be a safety hazard, although some of the fear associated with it is undeserved.
What type of wiring was used in the 1970s?
The 1970's were no exception. During the late 1960's through mid-1970's there was a worldwide shortage of copper - the preferred material used for house wiring. The industry turned to the next best conductor which is aluminum. It was readily available, less expensive than copper, and performs very well as a conductor.
What kind of wiring was used in 1900?
Unsourced material may be challenged and removed. Knob-and-tube wiring (sometimes abbreviated K&T) is an early standardized method of electrical wiring in buildings, in common use in North America from about 1880 to the 1930s.
How were houses wired in 1960?
Aluminum Wiring Before the 1960s, copper was the most common material used in household wiring. But a massive shortage left costs for this metal way too high for the average homeowner. As a result, builders turned to aluminum wiring in new construction.
Does a 60 year old house need rewiring?
If a property is more than 30 years old and has the original wiring, it is likely to need updating, at least in part, to meet modern standards, including replacing the fuse box with a modern consumer unit. A sign a rewire is necessary, is dated rubber, fabric or lead-insulated cabling.
What kind of wiring was used in 1920s?
Popular through 1920, knob-and-tube was a two-wire system held about one inch away from studs and joists by porcelain knobs, or protected by porcelain tubes where it crossed other wires or went through the framing. Knob-and-tube wiring contained no grounding and the outlets were not polarized.
What kind of wiring was used in 1910?
Knob-And-Tube Wiring Between 1890 and 1910, a wiring system known as knob-and-tube was the principal system of installation. It was quite a dependable system for the time, and a surprising number of American homes still have knob-and-tube wiring functioning, where it is often found alongside more modern updates.
Which wire is hot in old wiring?
black wireHere's a rundown of electrical wires: The black wire is the "hot" wire, it carries the electricity from the breaker panel into the switch or light source. The white wire is the "neutral" wire, it takes any unused electricity and current and sends it back to the breaker panel.
What is a two wire cable?
Two-Wire Plastic-Sheathed Cable. This early version of the modern ROMEX® cable consists of wires sheathed in plastic. The plastic can be easily damaged. Because it contains only two wires, it is impossible to add grounded devices to this system.
Can old insulating material rot?
Not only could old insulating material rot and expose hot wires, but systems that were designed to support a few lights and radios are now being asked to power computers, microwaves, hair dryers, refrigerators and many other modern devices. Before purchasing an old home, hire an electrician to evaluate the entire electrical system.
Do you need to replace aluminum wire?
Aluminum wire does not necessarily need to be replaced, but it is more likely to cause problems than other types and must be inspected and maintained. Problems can occur at connections, and if this has happened in the past the homeowner will often see signs of arcing in switches and outlets.
What color are NMC wires?
The exterior insulation on fabric-insulated NMC electrical wires are often black, silver, or white but may also be black or brown. The individual conductors within the cable may be insulated in rubber or fabric-covered rubber or they may be insulated by plastic in later wiring products. [Click to enlarge any image]
Who makes fabric insulated wire?
A widely-used brand of fabric-insulated electrical wire, often with internal conductors insulated in rubber was a silver-coated fabric wire produced by Paranite Electrical Wire corporation and marketed under the brand Paraflex.
What is Aaron's Ettco wire?
Aaron's Ettco wire looks like a paint-coated asphalt-impregnated-fabric sheathed electrical wire widely used from about 1949- 1975. In researching ETCOFLEX use of asbestos in wire insulation I have not found confirmation that asbestos was used.
When was Cresflex wire invented?
Cresflex was a brand of Crescent Insulated Wire & Cable Co., Inc., first trademarked in 1936, currently expired. Above is gray Cres-Flex® electrical wire in a photo provided by an InspectApedia.com reader.
Where is Paranite wire from?
This electrical wire is from a 1962-1963 home located in San Jose, California. An argument supporting possible presence of asbestos in Paranite products is the observation that Paranite, a producer as well of rubber pipe coupling, packing sheets, valves, hoses, was owned by Raybestos-Manhattan, Inc.
Who owns Cirtex wire?
1938, registered in 1956. Currently (2019) a similar brand, Cirtex® electrical wire is a brand owned by Marmon Wire & Cable Inc. , the 15th "new owner" of this electrical brand.
Can aluminum wire be used on more than one circuit?
Watch out: Aluminum wire may have been added for more than 1 circuit, and may not be so labeled. Often the use of #12 wire on what's usually a 15 amp circuit is a Clue.
What is wire in a house?
It helps to understand a few basic terms used to describe wiring. An electrical wire is a type of conductor, which is a material that conducts electricity. In the case of household wiring, the conductor itself is usually copper or aluminum (or copper-sheathed aluminum) and is either a solid metal conductor or stranded wire. Most wires in a home are insulated, meaning they are wrapped in a nonconductive plastic coating. One notable exception is ground wires, which are typically solid copper and are either insulated with green sheathing or uninsulated (bare).
How many wires are in a telephone cable?
Telephone cable may contain four or eight wires. Category 5 (Cat 5) cable, the most common type of household data wiring, contains eight wires wrapped together in four pairs. It can be used for both phone and data transmission and offers greater capacity and quality than standard phone wire .
What are THHN and THWN wires?
Neutral wires: White, brown. Ground wires: Green, yellow-green. THHN and THWN wires are circuit wires that should never be handled when the circuits are turned on.
What is low voltage wire?
Low-voltage wires typically are insulated and may be contained in cable sheathing or combined in twisted pairs, similar to lamp cord wire. It must be used only for low-voltage applications. These are typically very small wires that are much different from standard circuit wiring.
What is NM wire?
The most common type of wiring in modern homes is in the form of nonmetallic (NM) cable, which consists of two or more individual wires wrapped inside a protective plastic sheathing. NM cable usually contains one or more “hot” (current-carrying) wires, a neutral wire, and a ground wire.
What is the importance of knowing the wire type?
Knowing the basic wire types is essential to almost any electrical project around the house. When you're installing new wiring, for example, choosing the right wire or cable is half the battle. And when you’re examining existing wiring in your home, identifying the wire type can tell you a lot about the circuit the wiring belongs to—for example, ...
What is coaxial cable?
Coaxial cable is a round jacketed cable that features an inner conductor surrounded by a tubular insulating layer, surrounded by a tubular conducting shield made of braided wire. It can be identified by the threaded connectors that are used to make unions and device hookups.
What is the difference between a wire and a cable?
In fact they are quite different. A wire is made of a single electrical conductor while a cable is a group or bundle of multiple wires inside a common sheathing. Both of them are used for carrying electrical current. Nowadays due to the advancement in technology, almost everything is powered by electricity.
What sector uses wires and cables?
Not only the electrical sector uses cables and wires for power transmission and distribution to our house and industries, the Telecom sector also relies on various types of cables for uninterrupted data transmission.
What is twisted pair cable?
Twisted Pair Cable. This type of communication cable is made from two insulated wires twisted together to form a twisted pair. The purpose of twisting is to reduce the electromagnetic interference or noise. They are used in Ethernet network and telephone communication.
How many conductors does a quadruplex cable have?
Quadruplex Cable: The Quadruplex service drop cable is a quad or four core conductors. It has 4 conductors; three of them are insulated conductors for phase lines and a bare conductor for neutral line.
What is NM wire?
The non-metallic or NM sheathed wires are used for in-house wiring. It may consist of 2 or more than 2 insulated conductors with an insulated or bare ground conductor. There is another layer of plastic XLPE sheathing for more protection. The latest version NM type-B is currently used by electricians for interior installation. The conductors could be solid or stranded. The stranded conductors are easier to route through conduits.
Why is it important to label wires?
The labeling of the cables is very important and it provides a lot of information regarding its insulation types, numbers of wires and the gauge of the wires. Take a look at some of labels written on the wires commonly used in home wiring.
Why is twin lead cable important?
The conductors are held apart and uniformly space by a plastic layer between them. The equal spacing is very important because it keeps the signal from distortion. The conductors are mostly stranded to avoid skin effects and they are insulated using the same plastic material.
1. Non-Metallic Cable
A non-metallic, or NM cable, is one of the most common types of electrical wires in modern homes. These cables typically feature a hot wire, a ground wire, and a neutral wire in one sheathing. They’re also sometimes referred to as Romex cables.
2. Armored Cable
You may have heard armored cables called AC cables or BX wiring, but they’re all one in the same. This type of cable is often used in areas with stricter rules and regulations surrounding electrical codes, where NM cables may not be allowed. Armored cables are more expensive than NM cables, but they’re also sturdier and safer.
3. Metal-Clad Cable
Metal-clad cables, or MC cables, are covered in a protective metal sheath. This type of cable is sturdier than a typical NM cable and is suitable for areas that may be unfinished or exposed, such as basements.
5. Underground Feeder Cable
An underground feeder cable, or UF cable, is typically used to bring electricity to outdoor spaces. Unlike NM cables, the individual wires are wrapped in plastic and they’re protected against damage from moisture and sunlight.
6. Low-Voltage Wiring
As the name suggests, low-voltage wires are often used in areas where you don’t need much electricity. They’re suitable for circuits that use less than 50 volts. Some examples of where low-voltage wiring might make sense include very small appliances like doorbells and thermostats.
7. Phone and Data Wire
While most people exclusively use mobile phones, there are plenty of homes that still use a landline telephone. Most homes also use wifi to provide internet connection to their computers and other devices. For these communication setups, you’ll need telephone and data wires.
8. Coaxial Cable
Although coaxial cables are becoming less common, they’re still sometimes used to connect televisions with cable service or satellite dishes. They’re also sometimes used to transmit phone and internet data.
What metal is used in electrical wiring?
Metals Used in Wires. Through most of the history of residential electrical service, the preferred metal used in the conducting wires has been copper, known as the best conductor of electrical current. In the mid-1960s, when copper prices were quite high, aluminum came into vogue as a material for electrical wiring.
When did electrical service start?
Electrical service to American homes began in the late 1890s and blossomed from 1920 to 1935, by which time 70 percent of American homes were connected to the electrical utility grid. In the following 200 some years, the methods for installing wiring in those homes has seen several important innovations aimed at improving the safety ...
What is NM cable?
The form of NM cable was an update to older NM cable, incorporating the use of a bare copper grounding wire that joined the insulated hot and neutral wires contained within the sheathing. Instead of rubberized sheathing, modern NM cable uses a very tough and durable vinyl sheathing. This update made the MN cable inexpensive and very easy to install. It is a very flexible product and is used extensively in virtually every new home built.
What is flexible armored cable?
In the 1920s to 1940s, electrical installations took a turn to a more protective wiring scheme—flexible armored cable. Flex, also known as Greenfield, was a welcomed addition to home wiring because the flexible metal walls helped to protect the wires from damage, and also offered a metal pathway that could ground the system when properly installed. Although it was an improvement, this wiring method had its troubles. Although the individual wire conductors are protected, the flexible outer metal jacket serves as a proper ground only when the metal pathway is complete all the way to the service entrance and grounding rod. There is still no separate ground wire in these installations.
How long does sheathed cable last?
Early sheathed cable, however, also has an expected lifespan of about 25 years, and where it is still in use, such installations need to be upgraded.
When did knob and tube wiring start?
Knob-And-Tube Wiring. Between 1890 and 1910, a wiring system known as knob-and-tube was the principal system of installation. It was quite a dependable system for the time, and a surprising number of American homes still have knob-and-tube wiring functioning, where it is often found alongside more modern updates. Featured Video.
Can you buried feeder wire under the ground?
Underground feeder wire (UF) can be buried directly under the ground without the need for a protecting conduit. This type of wire has a hot, a neutral, and a ground wire embedded in a solid plastic vinyl sheath that protects it from moisture.
What to do if you don't have the budget to replace the electrical panel?
If you don’t have the budget to replace the electrical panel replacing circuit breakers with arc-fault circuit interrupters is another safeguard. These detect dangerous electrical arcs—abnormal sparks—and halt them before they can start a fire. Have your electrical system inspected by an experienced electrician.
Can wires be damaged?
Wiring, like the rest of us, will eventually deteriorate and become damaged with age. Be it chewed by mice, damaged by nails hammered haphazardly into walls or simple disintegration, a lack of insulation means exposed wires lurk that can lead to sparks and fire.
Is it safe to have an electrician inspect your house?
Electrical work is inherently dangerous, always call a professional, licensed electrician to perform electrical work in your house. These recommendations should not be considered an alternative to an actual electrical home inspection by a licensed electrical contractor. At all times follow electrical code requirements specific to your area.