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Electromagnetic Lock
An electromagnetic lock, magnetic lock, or maglock is a locking device that consists of an electromagnet and an armature plate. Operation The principle behind an electromagnetic lock is the use of electromagnetism to lock a door when energized. The holding force should be collinear with the load, and the lock and armature plate should be face-to-face to achieve optimal operation. The magnetic lock relies upon some of the basic concepts of electromagnetism. Essentially it consists of an electromagnet attracting a conductor with a force large enough to prevent the door from being opened. In a more detailed examination, the device makes use of the fact that a current through one or more loops of wire (known as a solenoid) produces a magnetic field. This works in free space, but if the solenoid is wrapped around a ferromagnetic core such as soft iron the effect of the field is greatly amplified. This is because the internal magnetic domains of the material align with each othe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Magnetic Lock
An electromagnetic lock, magnetic lock, or maglock is a Lock (security device), locking device that consists of an electromagnet and an armature plate. Operation The principle behind an electromagnetic lock is the use of electromagnetism to lock a door when energized. The holding force should be collinearity, collinear with the load, and the lock and armature plate should be face-to-face to achieve optimal operation. The magnetic lock relies upon some of the basic concepts of electromagnetism. Essentially it consists of an electromagnet attracting a conductor with a force large enough to prevent the door from being opened. In a more detailed examination, the device makes use of the fact that a current through one or more loops of wire (known as a solenoid) produces a magnetic field. This works in vacuum, free space, but if the solenoid is wrapped around a ferromagnetism, ferromagnetic core such as iron, soft iron the effect of the field is greatly amplified. This is because ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bracket (architecture)
A bracket is a structural or decorative architectural element that projects from a wall, usually to carry weight and sometimes to "strengthen an angle". It can be made of wood, stone, plaster, metal, or other media. A corbel or console are types of brackets. In mechanical engineering a bracket is any intermediate component for fixing one part to another, usually larger, part. What makes a bracket a bracket is that it is intermediate between the two and fixes the one to the other. Brackets vary widely in shape, but a prototypical bracket is the L-shaped metal piece that attaches a shelf (the smaller component) to a wall (the larger component): its vertical arm is fixed to one (usually large) element, and its horizontal arm protrudes outwards and holds another (usually small) element. This shelf bracket is effectively the same as the architectural bracket: a vertical arm mounted on the wall, and a horizontal arm projecting outwards for another element to be attached on top of it ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Montreal Forum
Montreal Forum () is a historic building located facing Cabot Square, Montreal, Cabot Square in Montreal, Quebec, Canada. Called "the most storied building in hockey history" by ''Sporting News'', it was an indoor arena which served as the home of the National Hockey League's Montreal Maroons from 1924 to 1938 and the Montreal Canadiens from 1926 to 1996. The Forum was built by the Brookfield Properties, Canadian Arena Company in 159 days. Today most of the Forum building is now a multiplex cinema known as ''Cineplex Cinemas Forum'' operated by Cineplex Entertainment. Additionally, a large portion of the building's upper floors are used as campus expansion for Dawson College. Located at the northeast corner of Atwater Avenue, Atwater and Saint Catherine Street, Ste-Catherine West (Atwater (Montreal Metro), Metro Atwater), the building was historically significant as 15 Stanley Cup championships were clinched/presented on its ice: twelve for the Canadiens and one for the Maroons (f ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Crash Bar
A crash bar (also known as a panic exit device, panic bar, or bump bar)American National Standards Institute, ANSI/BHMA A156.3-2001, American National Standard for Exit Devices is a type of door opening mechanism which allows users to open a door by pushing a bar. While originally conceived as a way to prevent crowd crushing in an emergency, crash bars are now used as the primary door opening mechanism in many commercial buildings. The device consists of a spring-loaded metal bar which is fixed horizontally to a door that swings in the direction of an exit. Depressing the bar unlatches the door, allowing occupants to quickly leave the building. Modern fire standards often mandate that doors be fitted with crash bars in commercial and other occupancies where mass evacuation may be slowed by other types of door openers. They are sometimes intended solely for emergency use and may be fitted with alarms. However, in many buildings the crash bar is the primary mechanism for open ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
National Fire Protection Association
The National Fire Protection Association (NFPA) is a U.S.-based international nonprofit organization devoted to eliminating death, injury, property damage, and economic loss due to fire, electrical, and related hazards. , the NFPA claims to have 50,000 members and 9,000 volunteers working with the organization through its 250 technical committees. History In 1895, a Committee on Automatic Sprinkler Protection was formed in Massachusetts by men affiliated with several fire insurance companies and a pipe manufacturer to develop a uniform standard for the design and installation of fire sprinkler systems. At the time, there were nine such standards in effect within of Boston, Massachusetts, and such diversity was causing great difficulties for plumbers working in the New England New England is a region consisting of six states in the Northeastern United States: Connecticut, Maine, Massachusetts, New Hampshire, Rhode Island, and Vermont. It is bordered by the state of New Y ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Incandescent Light Bulb
An incandescent light bulb, also known as an incandescent lamp or incandescent light globe, is an electric light that produces illumination by Joule heating a #Filament, filament until it incandescence, glows. The filament is enclosed in a glass bulb that is either vacuum, evacuated or filled with inert gas to protect the filament from oxidation. Electric current is supplied to the filament by terminals or wires embedded in the glass. A bulb socket provides mechanical support and electrical connections. Incandescent bulbs are manufactured in a wide range of sizes, light output, and voltage ratings, from 1.5 volts to about 300 volts. They require no external Regulator (automatic control), regulating equipment, have low manufacturing costs, and work equally well on either alternating current or direct current. As a result, the incandescent bulb became widely used in household and commercial lighting, for portable lighting such as table lamps, car headlamps, and flashlights, an ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Electric Strike
An electric strike is an access control device used for door frames. It replaces the fixed strike faceplate often used with a latch (also known as a ''keeper''). Description Like a fixed strike plate, an electric strike plate normally presents a ramped or beveled surface to the locking latch allowing the door to close and latch just like a fixed strike would. However, an electric strike's ramped surface can, upon command, pivot out of the way when the lock on the door is in the locked position and the door is opened, allowing a user to pull/push the door to open it without operating the mechanical lock or using a mechanical key. After the door is opened past the keeper, the keeper returns to its standard position and re-locks when power is removed or applied, depending upon the strike's configuration. Variations Electric strikes are generally available in two configurations: * Fail-secure. Also called fail-locked or non-fail safe. In this configuration, applying electric c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Electric Current
An electric current is a flow of charged particles, such as electrons or ions, moving through an electrical conductor or space. It is defined as the net rate of flow of electric charge through a surface. The moving particles are called charge carriers, which may be one of several types of particles, depending on the Electrical conductor, conductor. In electric circuits the charge carriers are often electrons moving through a wire. In semiconductors they can be electrons or Electron hole, holes. In an Electrolyte#Electrochemistry, electrolyte the charge carriers are ions, while in Plasma (physics), plasma, an Ionization, ionized gas, they are ions and electrons. In the International System of Units (SI), electric current is expressed in Unit of measurement, units of ampere (sometimes called an "amp", symbol A), which is equivalent to one coulomb per second. The ampere is an SI base unit and electric current is a ISQ base quantity, base quantity in the International System of Qua ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Diode Bridge
A diode bridge is a bridge rectifier circuit of four diodes that is used in the process of converting alternating current (AC) from the input terminals to direct current (DC, i.e. fixed polarity) on the output terminals. Its function is to convert the negative voltage portions of the AC waveform to positive voltage, after which a low-pass filter can be used to smooth the result into DC. When used in its most common application, for conversion of an alternating-current (AC) input into a direct-current (DC) output, it is known as a bridge rectifier. A bridge rectifier provides full-wave rectification from a two-wire AC input, resulting in lower cost and weight as compared to a rectifier with a three-wire input from a transformer with a center-tapped secondary winding. Prior to the availability of integrated circuits, a bridge rectifier was constructed from separate diodes. Since about 1950, a single four-terminal component containing the four diodes connected in a bridge con ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fire Safety
Fire safety is the set of practices intended to reduce destruction caused by fire. Fire safety measures include those that are intended to prevent wikt:ignition, the ignition of an uncontrolled fire and those that are used to limit the spread and impact of a fire. Fire safety measures include those that are planned during the construction of a building or implemented in structures that are already standing and those that are taught or provided to occupants of the building. Threats to fire safety are commonly referred to as fire hazards. A fire hazard may include a situation that increases the likelihood of a fire or may impede fire escape, escape in the event a fire occurs. Fire safety is often a component of building code, building safety. Those who inspect buildings for violations of the Fire Code and go into schools to educate children on fire safety topics are Fire Department members known as ''Fire Prevention Officers''. The Chief Fire Prevention Officer or Chief of Fire ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Keycard Lock
A keycard lock is a lock operated by a keycard, a flat, rectangular plastic card. The card typically, but not always, has identical dimensions to that of a credit card, that is ID-1 format. The card stores a physical or digital pattern that the door mechanism accepts before disengaging the lock. There are several common types of keycards in use, including the mechanical holecard, barcode, magnetic stripe, Wiegand wire embedded cards, smart card (embedded with a read/write electronic microchip), RFID, and NFC proximity cards. Keycards are frequently used in hotels as an alternative to mechanical keys. The first commercial use of key cards was to raise and lower the gate at automated parking lots where users paid a monthly fee. Overview Keycard systems operate by physically moving detainers in the locking mechanism with the insertion of the card, by shining LEDs through a pattern of holes in the card and detecting the result, by swiping or inserting a magnetic stripe ca ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Security Alarm
A security alarm is a system designed to detect intrusions, such as unauthorized entry, into a building or other areas, such as a home or school. Security alarms protect against burglary (theft) or property damage, as well as against intruders. Examples include personal systems, neighborhood security alerts, car alarms, and prison alarms. Some alarm systems serve a single purpose of burglary protection; combination systems provide Fire alarm system, fire and intrusion protection. Intrusion-alarm systems are combined with closed-circuit television surveillance (CCTV) systems to record intruders' activities and interface to access control systems for electrically locked doors. There are many types of security systems. Homeowners typically have small, self-contained noisemakers. These devices can also be complicated, multirole systems with computer and network surveillance, computer monitoring and control. It may even include a two-way voice which allows communication between the pa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
