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An electrical conduit is a tube used to protect and route electrical wiring in a building or structure. Electrical conduit may be made of metal, plastic, fiber, or fired clay. Most conduit is rigid, but flexible conduit is used for some purposes. Conduit is generally installed by electricians at the site of installation of electrical equipment.
This is specially true of bushings around high-voltage conductors. The electrical analysis usually focusses on the creation of the electric field around the conductor and how the shape of the bushing effects that field. The structural analysis considers the loads (wind, snow, earthquakes, rain, etc.) that the bushing is expected to survive.
The conduit methods were known to be of better quality, but cost significantly more than K&T. [2] In 1909, flexible armored cable cost about twice as much as K&T, and conduit cost about three times the price of K&T. [6] Knob and tube wiring persisted since it allowed owners to wire a building for electricity at lower cost.
The first electrical codes arose in the 1880s with the commercial introduction of electrical power; however, many conflicting standards existed for the selection of wire sizes and other design rules for electrical installations, and a need was seen to introduce uniformity on the grounds of safety.
In commercial and industrial, unenclosed NM cable is often prohibited in certain areas or altogether (depending on what the building is used for and local/state building codes). Therefore, it is almost never used by commercial electrical contractors. Most wiring is put in non-flexible conduit, usually EMT because of its cost and durability.
IEC 60364 Electrical Installations for Buildings is the International Electrotechnical Commission (IEC)'s international standard on electrical installations of buildings.This standard is an attempt to harmonize national wiring standards in an IEC standard and is published in the European Union by CENELEC as "HD 60364".
Circuit integrity describes the extent of a fire's effect on an electrical circuit's operation. It is a form of fire-resistance rating. Circuit integrity is achieved via passive fire protection means, which are subject to listing and approval use and compliance.
A fish tape (also called a draw wire, draw tape, or an electrician ' s snake) is a tool used by electricians to route new wiring through walls and electrical conduit. [1]Made of a narrow band of spring steel, by careful manipulation, the tape can be guided through confined spaces such as wall cavities or conduits in many countries.