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Bootleg Ground
In building wiring installed with separate neutral and protective ground bonding conductors (a TN-S network), a bootleg ground (or a false ground) is a connection between the neutral side of a receptacle or light fixture and the ground lug or enclosure of the wiring device. Description A bootleg ground connects the neutral side of the receptacle to the conductive casing of an appliance or lamp. This can be a hazard because the neutral wire is a current-carrying conductor, which means the exposed casing can become energized. In addition, a fault condition to a bootleg ground will not trip a GFCI breaker, nor protect a receptacle that is wired from the load side of a GFCI receptacle. Before 1996, in the United States it was common to ground the frames of large 120/240-volt permanently-connected appliances (such as a clothes dryer or oven) to neutral conductors. This has been prohibited in new installations since the 1996 National Electrical Code (upon local adoption by legi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bootleg Ground
In building wiring installed with separate neutral and protective ground bonding conductors (a TN-S network), a bootleg ground (or a false ground) is a connection between the neutral side of a receptacle or light fixture and the ground lug or enclosure of the wiring device. Description A bootleg ground connects the neutral side of the receptacle to the conductive casing of an appliance or lamp. This can be a hazard because the neutral wire is a current-carrying conductor, which means the exposed casing can become energized. In addition, a fault condition to a bootleg ground will not trip a GFCI breaker, nor protect a receptacle that is wired from the load side of a GFCI receptacle. Before 1996, in the United States it was common to ground the frames of large 120/240-volt permanently-connected appliances (such as a clothes dryer or oven) to neutral conductors. This has been prohibited in new installations since the 1996 National Electrical Code (upon local adoption by legi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Building Wiring
Electrical wiring is an electrical installation of cabling and associated devices such as switches, distribution boards, sockets, and light fittings in a structure. Wiring is subject to safety standards for design and installation. Allowable wire and cable types and sizes are specified according to the circuit operating voltage and electric current capability, with further restrictions on the environmental conditions, such as ambient temperature range, moisture levels, and exposure to sunlight and chemicals. Associated circuit protection, control, and distribution devices within a building's wiring system are subject to voltage, current, and functional specifications. Wiring safety codes vary by locality, country, or region. The International Electrotechnical Commission (IEC) is attempting to harmonise wiring standards among member countries, but significant variations in design and installation requirements still exist. Wiring codes of practice and regulations Wiring i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Earthing System
An earthing system (UK and IEC) or grounding system (US) connects specific parts of an electric power system with the ground, typically the Earth's conductive surface, for safety and functional purposes. The choice of earthing system can affect the safety and electromagnetic compatibility of the installation. Regulations for earthing systems vary among countries, though most follow the recommendations of the International Electrotechnical Commission (IEC). Regulations may identify special cases for earthing in mines, in patient care areas, or in hazardous areas of industrial plants. In addition to electric power systems, other systems may require grounding for safety or function. Tall structures may have lightning rods as part of a system to protect them from lightning strikes. Telegraph lines may use the Earth as one conductor of a circuit, saving the cost of installation of a return wire over a long circuit. Radio antennas may require particular grounding for operation, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
AC Power Plugs And Sockets
AC power plugs and sockets connect electric equipment to the alternating current (AC) mains electricity power supply in buildings and at other sites. Electrical plugs and sockets differ from one another in voltage and current rating, shape, size, and connector type. Different standard systems of plugs and sockets are used around the world. Plugs and sockets for portable appliances became available in the 1880s, to replace connections to light sockets with wall-mounted outlets. A proliferation of types developed for both convenience and protection from electrical injury. Today there are about 20 types in common use around the world, and many obsolete socket types are found in older buildings. Coordination of technical standards has allowed some types of plug to be used across large regions to facilitate trade in electrical appliances, and for the convenience of travellers and consumers of imported electrical goods. Some multi-standard sockets allow use of several types of plug; ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Residual-current Device
A residual-current device (RCD), residual-current circuit breaker (RCCB) or ground fault circuit interrupter (GFCI) is an electrical safety device that quickly breaks an electrical circuit with leakage current to ground. It is to protect equipment and to reduce the risk of serious harm from an ongoing electric shock. Injury may still occur in some cases, for example if a human receives a brief shock before the electrical circuit is isolated, falls after receiving a shock, or if the person touches both conductors at the same time. If the RCD device has additional overcurrent protection integrated in the same device, it is referred to as RCBO. An earth leakage circuit breaker may be a RCD, although an older type of voltage-operated earth leakage circuit breaker (ELCB) also exists. These electrical wiring devices are designed to quickly and automatically isolate a circuit when it detects that the electric current is unbalanced between the supply and return conductors of a ci ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Clothes Dryer
A clothes dryer, also known as tumble dryer or simply dryer, is a powered household appliance that is used to remove moisture from a load of clothing, bedding and other textiles, usually shortly after they are washed in a washing machine. Many dryers consist of a rotating drum called a "tumbler" through which heated air is circulated to evaporate the moisture, while the tumbler is rotated to maintain air space between the articles. Using these machines may cause clothes to shrink or become less soft (due to loss of short soft fibers). A simpler non-rotating machine called a "drying cabinet" may be used for delicate fabrics and other items not suitable for a tumble dryer. Drying at a minimum of heat for thirty minutes kills many parasites including house dust mites,Mahakittikun, V; Boitano, JJ; Ninsanit, P; Wangapai, T; Ralukruedej, K (December 2011). "Effects of high and low temperatures on development time and mortality of house dust mite eggs". Experimental & Applied Acarology. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Oven
upA double oven A ceramic oven An oven is a tool which is used to expose materials to a hot environment. Ovens contain a hollow chamber and provide a means of heating the chamber in a controlled way. In use since antiquity, they have been used to accomplish a wide variety of tasks requiring controlled heating. Because they are used for a variety of purposes, there are many different types of ovens. These types differ depending on their intended purpose and based upon how they generate heat. Ovens are often used for cooking, where they can be used to heat food to a desired temperature. Ovens are also used in the manufacturing of ceramics and pottery; these ovens are sometimes referred to as kilns. Metallurgical furnaces are ovens used in the manufacturing of metals, while glass furnaces are ovens used to produce glass. There are many methods by which different types of ovens produce heat. Some ovens heat materials using the combustion of a fuel, such as wood, coal, or na ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
National Electrical Code
The National Electrical Code (NEC), or NFPA 70, is a regionally adoptable standard for the safe installation of electrical wiring and equipment in the United States. It is part of the National Fire Code series published by the National Fire Protection Association (NFPA), a private trade association. Despite the use of the term "national", it is not a Law of the United States, federal law. It is typically adopted by U.S. state, states and municipalities in an effort to standardize their enforcement of safe electrical practices. In some cases, the NEC is amended, altered and may even be rejected in lieu of regional regulations as voted on by local governing bodies. The "authority having jurisdiction" inspects for compliance with these standards. The NEC should not be confused with the National Electrical Safety Code (NESC) published by the Institute of Electrical and Electronics Engineers (IEEE). The NESC is used for electric power and communication utility systems including overh ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Receptacle Tester
An electrical outlet tester, receptacle tester, or socket tester is a small device containing a 3-prong power plug and three indicator lights, used for quickly detecting some types of incorrectly-wired electrical wall outlets or campsite supplies. The tester is easily carried in a pocket, can be used with little training, and can identify some common wiring problems, but it fails to detect certain other dangerous types of wiring defects. Tests and limitations The outlet tester checks that each contact in the outlet appears to be connected to the correct wire in the building's electrical wiring. It can identify several common wiring errors, including swapped phase and neutral, and failure to connect ground. The tester confirms continuity and polarity of the electrical connections, but it does not verify current-carrying ability, electrical safety (which requires impedance testing), insulation breakdown voltage, or loop connection of ring mains. Simple three-light testers ca ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Circuit Breaker
A circuit breaker is an electrical safety device designed to protect an electrical circuit from damage caused by an overcurrent or short circuit. Its basic function is to interrupt current flow to protect equipment and to prevent the risk of fire. Unlike a fuse, which operates once and then must be replaced, a circuit breaker can be reset (either manually or automatically) to resume normal operation. Circuit breakers are made in varying sizes, from small devices that protect low-current circuits or individual household appliances, to large switchgear designed to protect high voltage circuits feeding an entire city. The generic function of a circuit breaker, or fuse, as an automatic means of removing power from a faulty system, is often abbreviated as OCPD (Over Current Protection Device). Origins An early form of circuit breaker was described by Thomas Edison in an 1879 patent application, although his commercial power distribution system used fuses. Its purpose was to pro ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Arc-fault Circuit Interrupter
An arc-fault circuit interrupter (AFCI) or arc-fault detection device (AFDD) is a circuit breaker that breaks the circuit when it detects the electric arcs that are a signature of loose connections in home wiring. Loose connections, which can develop over time, can sometimes become hot enough to ignite house fires. An AFCI selectively distinguishes between a harmless arc (incidental to normal operation of switches, plugs, and brushed motors), and a potentially dangerous arc (that can occur, for example, in a lamp cord which has a broken conductor). In Canada and the United States, AFCI breakers have been required by the electrical codes for circuits feeding electrical outlets in residential bedrooms since the beginning of the 21st century; the US '' National Electrical Code'' has required them to protect most residential outlets since 2014, and the '' Canadian Electrical Code'' has since 2015. In regions using 230 V, the combination of higher voltage and lower load currents ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Electrical Wiring In North America
Electrical wiring in North America follows the regulations and standards applicable at the installation location. It is also designed to provide proper function, and is also influenced by history and traditions of the location installation. The US National Electrical Code is applicable to many areas in the US where state, county or local authorities have adopted it. For electrical wiring in Canada, the Canadian Electrical Code is a very similar standard published in Canada by the Canadian Standards Association. Terminology Although much of the electrician's field terminology matches that of the electrical codes, usages can vary: * Neutral wire is the return conductor of a circuit; in building wiring systems, the neutral wire is connected to earth ground at only one point. North American standards state that the neutral is neither switched nor fused except in very narrowly defined circumstances. The neutral is connected to the center tap of the power company transformer of a spli ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
