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Electrical Room
An electrical room is a technical room or space in a building dedicated to electrical equipment. Its size is usually proportional to the size of the building; large buildings may have a main electrical room and subsidiary electrical rooms. Electrical equipment may be for power distribution equipment, or for communications equipment.Albert Thumann, Harry Franz, ''Efficient Electrical System Design Handbook'', Fiarmont Press 2009 pages 76-77 Electrical rooms typically house the following equipment: * Electric switchboards * Distribution boards *Circuit breakers and disconnects * Motor control centers *Transformers * Busbars *Electricity meters * Backup batteries in a Battery room * Fire alarm control panels *Distribution frames In large building complexes, the primary electrical room may house an indoor electrical substation. Construction features The construction features of an electrical room vary depending on the scope of the equipment to be installed. Floors may be reinfo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Electrical Switchgear
Electricity is the set of physical phenomena associated with the presence and motion of matter possessing an electric charge. Electricity is related to magnetism, both being part of the phenomenon of electromagnetism, as described by Maxwell's equations. Common phenomena are related to electricity, including lightning, static electricity, electric heating, electric discharges and many others. The presence of either a positive or negative electric charge produces an electric field. The motion of electric charges is an electric current and produces a magnetic field. In most applications, Coulomb's law determines the force acting on an electric charge. Electric potential is the work done to move an electric charge from one point to another within an electric field, typically measured in volts. Electricity plays a central role in many modern technologies, serving in electric power where electric current is used to energise equipment, and in electronics dealing with electrical c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Busbar
In electric power distribution, a busbar (also bus bar) is a metallic strip or bar, typically housed inside switchgear, panel boards, and busway enclosures for local high current power distribution. They are also used to connect high voltage equipment at electrical switchyards, and low-voltage equipment in battery banks. They are generally uninsulated, and have sufficient stiffness to be supported in air by insulated pillars. Those features allow sufficient cooling of the conductors, and the ability to tap in at various points without having to create a new joint. Design and placement The busbar's material composition and cross-sectional size determine the maximum current it can safely carry. Busbars can have a cross-sectional area of as little as , but electrical substations may use metal tubes in diameter or more as busbars. Aluminium smelters use very large busbars to carry tens of thousands of amperes to the electrochemical cells that produce aluminium from molten ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Electrical Enclosure
An electrical enclosure is a cabinet for electrical or electronic equipment to mount switches, knobs and displays and to prevent electrical shock to equipment users and protect the contents from the environment. The enclosure is the only part of the equipment which is seen by users. It may be designed not only for its utilitarian requirements, but also to be pleasing to the eye. Regulations may dictate the features and performance of enclosures for electrical equipment in hazardous areas, such as petrochemical plants or coal mines. Electronic packaging may place many demands on an enclosure for heat dissipation, radio frequency interference and electrostatic discharge protection, as well as functional, esthetic and commercial constraints. Standards Internationally, IEC 60529 classifies the IP Codes (ingress protection rating) of enclosures. In the United States, the National Electrical Manufacturers Association (NEMA) publishes NEMA enclosure type standards for the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Utility Vault
A utility vault is an underground room providing access to subterranean public utility equipment, such as valves for water or natural gas pipes, or switchgear for electrical or telecommunications equipment. A vault is often accessible directly from a street, sidewalk or other outdoor space, thereby distinct from a basement of a building.City of New York, New York. ''2014 Construction Codes.'' Building Code, Chapter 32"Section 3201.8. Definitions.""Vault: Any space below the surface of a street, that is covered over, except those openings that are used exclusively as places for descending, by means of steps, to the cellar or basement of any building." Accessed 2018-04-09. Utility vaults are commonly constructed out of reinforced concrete boxes, poured concrete or brick. Small ones are usually entered through a manhole or grate on the topside and closed up by a manhole cover. Such vaults are considered confined spaces and can be hazardous to enter. Large utility vaults are simila ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Electrical Equipment In Hazardous Areas
In electrical engineering, electrical and safety engineering, safety engineering, hazardous locations (HazLoc, pronounced ''haz·lōk'') are places where fire or explosion hazards may exist. Sources of such hazards include gases, vapors, dust explosion, dust, fibers, and flyings, which are combustibility and flammability, combustible or flammable. Electrical equipment installed in such locations can provide an ignition source, due to electrical arcing, or high temperatures. Technical standard, Standards and regulations exist to identify such locations, classify the hazards, and design equipment for safe use in such locations. Overview A light switch may cause a small, harmless spark when switched on or off. In an ordinary household this is of no concern, but if a flammable atmosphere is present, the arc might start an explosion. In many industrial, commercial, and scientific settings, the presence of such an atmosphere is a common, or at least commonly possible, occurrence. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Live Terminal
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 methods Materials for wiring interior ele ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Building Code
A building code (also building control or building regulations) is a set of rules that specify the standards for construction objects such as buildings and non-building structures. Buildings must conform to the code to obtain planning permission, usually from a local council. The main purpose of building codes is to protect public health, safety and general welfare as they relate to the construction and occupancy of buildings and for example, the building codes in many countries require engineers to consider the effects of soil liquefaction in the design of new buildings. The building code becomes law of a particular jurisdiction when formally enacted by the appropriate governmental or private authority. Building codes are generally intended to be applied by architects, engineers, interior designers, constructors and regulators but are also used for various purposes by safety inspectors, environmental scientists, real estate developers, subcontractors, manufacturers of b ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Access Control
In physical security and information security, access control (AC) is the action of deciding whether a subject should be granted or denied access to an object (for example, a place or a resource). The act of ''accessing'' may mean consuming, entering, or using. It is often used interchangeably with authorization, although the authorization may be granted well in advance of the access control decision. Access control on digital platforms is also termed admission control. The protection of external databases is essential to preserve digital security. Access control is considered to be a significant aspect of privacy that should be further studied. Access control policy (also access policy) is part of an organization’s security policy. In order to verify the access control policy, organizations use an access control model. General security policies require designing or selecting appropriate security controls to satisfy an organization's risk appetite - access policies ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Electromagnetic Shielding
In electrical engineering, electromagnetic shielding is the practice of reducing or redirecting the electromagnetic field (EMF) in a space with barriers made of conductive or magnetic materials. It is typically applied to enclosures, for isolating electrical devices from their surroundings, and to cables to isolate wires from the environment through which the cable runs (). Electromagnetic shielding that blocks radio frequency (RF) electromagnetic radiation is also known as RF shielding. EMF shielding serves to minimize electromagnetic interference. The shielding can reduce the coupling of radio waves, electromagnetic fields, and electrostatic fields. A conductive enclosure used to block electrostatic fields is also known as a '' Faraday cage''. The amount of reduction depends very much upon the material used, its thickness, the size of the shielded volume and the frequency of the fields of interest and the size, shape and orientation of holes in a shield to an incident elec ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lightning Protection
A lightning rod or lightning conductor (British English) is a metal rod mounted on a structure and intended to protect the structure from a lightning strike. If lightning hits the structure, it is most likely to strike the rod and be conducted to ground through a wire, rather than passing through the structure, where it could start a fire or even cause electrocution. Lightning rods are also called finials, air terminals, or strike termination devices. In a lightning protection system, a lightning rod is a single component of the system. The lightning rod requires a connection to the earth to perform its protective function. Lightning rods come in many different forms, including hollow, solid, pointed, rounded, flat strips, or even bristle brush-like. The main attribute common to all lightning rods is that they are all made of conductive materials, such as copper and aluminum. Copper and its alloys are the most common materials used in lightning protection. History The first ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Stray Voltage
Stray voltage is the occurrence of electrical potential between two objects that ideally should not have any voltage difference between them. Small voltages often exist between two grounded objects in separate locations by the normal current flow in the power system. Contact voltage is a better defined term when large voltage appear as a result of a fault. Contact voltage on the enclosure of electrical equipment can appear from a fault in the electrical power system, such as a failure of insulation. Terminology The terminology, stray voltage may be used in any case of undesirable elevated electrical potential. More precise terminology gives an indication of the source of the voltage. Neutral to earth voltage (NEV) specifically refers to a difference in potential between a locally grounded object and the grounded return conductor, or neutral, of an electrical system. The neutral is theoretically at 0 V potential, as any grounded object, but current flows on the neutral b ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gaseous Fire Suppression
Gaseous fire suppression, also called clean agent fire suppression, is the use of inert gases and chemical agents to extinguish a fire. These agents are governed by the National Fire Protection Association (NFPA) Standard for Clean Agent Fire Extinguishing Systems – NFPA 2001 in the US, with different standards and regulations elsewhere. The system typically consists of the agent, agent storage containers, agent release valves, fire detectors, fire detection system (wiring control panel, actuation signaling), agent delivery piping, and agent dispersion nozzles. Theory There are four means used by the agents to extinguish a fire. They act on the " fire tetrahedron": * Reduction or isolation of fuel. No agents currently use this as the primary means of fire suppression. * Reduction of heat. Representative agents: Clean agent FS 49 C2 (NAF S 227, MH227, FM-200), Novec 1230, pentafluoroethane (NAF S125, ECARO-25). * Reduction or isolation of oxygen: Representative agents: IG-0 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
