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Motor Controller
A motor controller is a device or group of devices that can coordinate in a predetermined manner the performance of an electric motor. A motor controller might include a manual or automatic means for starting and stopping the motor, selecting forward or reverse rotation, selecting and regulating the speed, regulating or limiting the torque, and protecting against overloads and electrical faults. Motor controllers may use electromechanical switching, or may use power electronics devices to regulate the speed and direction of a motor. Applications Motor controllers are used with both DC motors (direct current) and AC motors (alternating current). A controller includes means to connect the motor's windings to the electrical power supply, and may also include overload, over-current, and oveheating protection and wiring (i.e. magnetic starter). A motor controller may also supervise the motor's field circuit, or detect conditions such as low supply voltage, incorrect polarity or in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Electric Motor
An electric motor is a machine that converts electrical energy into mechanical energy. Most electric motors operate through the interaction between the motor's magnetic field and electric current in a electromagnetic coil, wire winding to generate Laplace force in the form of torque applied on the motor's shaft. An electric generator is mechanically identical to an electric motor, but operates in reverse, converting mechanical energy into electrical energy. Electric motors can be powered by direct current (DC) sources, such as from batteries or rectifiers, or by alternating current (AC) sources, such as a power grid, Inverter (electrical), inverters or electrical generators. Electric motors may also be classified by considerations such as power source type, construction, application and type of motion output. They can be brushed motor, brushed or brushless motor, brushless, single-phase electric power, single-phase, two-phase electric power, two-phase, or three-phase electric p ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Korndörfer Autotransformer Starter
In electrical engineering, the Korndorfer starter is a technique used for reduced voltage soft starting of induction motors. The circuit uses a three-phase autotransformer and three three-phase switches. This motor starting method has been updated and improved by Hilton Raymond Bacon. Operation The Korndorfer starter can be used manually. Newer devices provide full automatic operation, which in addition would have: triple-pole line contactor (switch), start contactor, running contactor, three single-pole overload relays, autotransformer with a set tap-changing links, a suitable timer, and ''start'' and ''stop'' pushbuttons. If all switches are open the motor is completely disconnected from the three-phase network. To start the motor, first the switches 1 and 2 are closed. This supplies the motor a lower voltage from the autotransformer. The lower voltage limits the input current to the initially stationary motor, which accelerates. The torque of the motor is also lowered. The ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Canon PowerShot S45 - Main Board - Rohm BD6753KV-91775
Canon or Canons may refer to: Arts and entertainment * Canon (fiction), the material accepted as officially written by an author or an ascribed author * Literary canon, an accepted body of works considered as high culture ** Western canon, the body of high culture literature, music, philosophy, and works of art that is highly valued in the West * Canon of proportions, a formally codified set of criteria deemed mandatory for a particular artistic style of figurative art * Canon (music), a type of composition * Canon (hymnography), a type of hymn used in Eastern Orthodox Christianity. * ''Canon'' (album), a 2007 album by Ani DiFranco * ''Canon'' (film), a 1964 Canadian animated short * ''Canon'' (manga), by Nikki * Canonical plays of William Shakespeare * ''The Canon'' (Natalie Angier book), a 2007 science book by Natalie Angier * ''The Canon'' (podcast), concerning film Brands and enterprises * Canon Inc., a Japanese imaging and optical products corporation * Château ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pulse-width Modulation
Pulse-width modulation (PWM), also known as pulse-duration modulation (PDM) or pulse-length modulation (PLM), is any method of representing a signal as a rectangular wave with a varying duty cycle (and for some methods also a varying period). PWM is useful for controlling the average power or amplitude delivered by an electrical signal. The average value of voltage (and current) fed to the load is controlled by switching the supply between 0 and 100% at a rate faster than it takes the load to change significantly. The longer the switch is on, the higher the total power supplied to the load. Along with maximum power point tracking (MPPT), it is one of the primary methods of controlling the output of solar panels to that which can be utilized by a battery. PWM is particularly suited for running inertial loads such as motors, which are not as easily affected by this discrete switching. The goal of PWM is to control a load; however, the PWM switching frequency must be sele ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Electromotive Force
In electromagnetism and electronics, electromotive force (also electromotance, abbreviated emf, denoted \mathcal) is an energy transfer to an electric circuit per unit of electric charge, measured in volts. Devices called electrical ''transducers'' provide an emf by Energy transformation, converting other forms of energy into electrical energy. Other types of electrical equipment also produce an emf, such as Battery (electricity), batteries, which convert chemical energy, and Electric generator, generators, which convert mechanical energy. This energy conversion is achieved by Force, physical forces applying Work (physics), physical work on electric charges. However, electromotive force itself is not a physical force, and ISO/International Electrotechnical Commission, IEC standards have deprecated the term in favor of source voltage or source tension instead (denoted U_s). An Hydraulic analogy, electronic–hydraulic analogy may view emf as the mechanical work done to water by a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rotor (electric)
The rotor is a moving component of an electromagnetic system in the electric motor, electric generator, or alternator. Its rotation is due to the interaction between the windings and magnetic fields which produces a torque around the rotor's axis.Staff. "Understanding Alternators. What Is an Alternator and How Does It Work." N.p., n.d. Web. 24 November 2014 . Early development An early example of electromagnetic rotation was the first rotary machine built by Ányos Jedlik with electromagnets and a commutator, in 1826-27. Other pioneers in the field of electricity include Hippolyte Pixii who built an alternating current generator in 1832, and William Ritchie's construction of an electromagnetic generator with four rotor coils, a commutator and brushes, also in 1832. Development quickly included more useful applications such as Moritz Hermann Jacobi's motor that could lift 10 to 12 pounds with a speed of one foot per second, about 15 watts of mechanical power in 1834. In 18 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hall Effect Sensor
A Hall effect sensor (also known as a Hall sensor or Hall probe) is any sensor incorporating one or more Hall elements, each of which produces a voltage proportional to one axial component of the Magnetic field#The B-field, magnetic field vector using the Hall effect (named for physicist Edwin Hall). Hall sensors are used for proximity sensing, positioning (navigation), positioning, Speed limit enforcement, speed detection, and current sensing applications and are common in industrial and consumer applications. Hundreds of millions of Hall sensor integrated circuits (ICs) are sold each year by about 50 manufacturers, with the global market around a billion United States dollar, dollars. Principles In a Hall sensor, a fixed DC current, DC bias current is applied along one axis across a thin strip of metal called the Hall element transducer. Sensing electrodes on opposite sides of the Hall element along ''another'' axis measure the difference in electric potential (voltage) ac ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Encoder (position)
An encoder is a sensor which turns a position into an electronic signal. There are two forms: * Absolute encoders give an absolute position value. * Incremental encoders count movement rather than position. With detection of a datum position and the use of a counter, an absolute position may be derived. The position may be measured as either linear or angular position * Linear encoder, converts linear position to an electronic signal * Rotary encoder A rotary encoder, also called a shaft encoder, is an electro-mechanical device that converts the angle, angular position or motion of a shaft or axle to Analog signal, analog or Digital signal, digital output signals. There are two main types of ..., converts rotary position to an electronic signal See also * Encoder (other) {{Set index ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Solder
Solder (; North American English, NA: ) is a fusible alloy, fusible metal alloy used to create a permanent bond between metal workpieces. Solder is melted in order to wet the parts of the joint, where it adheres to and connects the pieces after cooling. Metals or alloys suitable for use as solder should have a lower melting point than the pieces to be joined. The solder should also be resistant to oxidative and corrosive effects that would degrade the joint over time. Solder used in making electrical connections also needs to have favorable electrical characteristics. Soft solder typically has a melting point range of , and is commonly used in electronics, plumbing, and sheet metal work. Alloys that melt between are the most commonly used. Soldering performed using alloys with a melting point above is called "hard soldering", "silver soldering", or brazing. In specific proportions, some alloys are eutectic — that is, the alloy's melting point is the lowest possible for a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Eutectic System
A eutectic system or eutectic mixture ( ) is a type of a homogeneous mixture that has a melting point lower than those of the constituents. The lowest possible melting point over all of the mixing ratios of the constituents is called the ''eutectic temperature''. On a phase diagram, the eutectic temperature is seen as the eutectic point (see plot on the right). Non-eutectic mixture ratios have different melting temperatures for their different constituents, since one component's lattice will melt at a lower temperature than the other's. Conversely, as a non-eutectic mixture cools down, each of its components solidifies into a lattice at a different temperature, until the entire mass is solid. A non-eutectic mixture thus does not have a single melting/freezing point temperature at which it changes phase, but rather a temperature at which it changes between liquid and slush (known as the liquidus) and a lower temperature at which it changes between slush and solid (the solidu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bimetallic Strip
A bimetallic strip or bimetal strip is a strip that consists of two strips of different metals which expand at different rates as they are heated. The different expansion rates cause the strip to bend one way if heated, and in the opposite direction if cooled below its initial temperature. Thus, a bimetal strip converts a temperature change into mechanical displacement. The metal with the higher coefficient of thermal expansion is on the outer side of the curve when the strip is heated and on the inner side when cooled. Common applications include temperature sensing (thermometer) and regulation (thermostat). The invention of the bimetallic strip is generally credited to John Harrison, an eighteenth-century clockmaker who made it for his third marine chronometer (H3) of 1759 to compensate for temperature-induced changes in the balance spring. Harrison's invention is recognized in the memorial to him in Westminster Abbey, England. Characteristics The strip consists of two st ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Volt-ampere Reactive
The volt-ampere ( SI symbol: VA, sometimes V⋅A or V A) is the unit of measurement for apparent power in an electrical circuit. It is the product of the root mean square voltage (in volts) and the root mean square current (in amperes). Volt-amperes are usually used for analyzing alternating current (AC) circuits. In direct current (DC) circuits, this product is equal to the real power, measured in watts. The volt-ampere is dimensionally equivalent to the watt: in SI units, 1 V⋅A = 1 W. VA rating is most used for generators and transformers, and other power handling equipment, where loads may be reactive (inductive or capacitive). Formulation For a simple electrical circuit running on direct current, the electrical current and voltage are constant. In that case, the real power (''P'', measured in watts) is the product of the current (''I'', measured in amperes) and the voltage from one side of the circuit to the other (''V'', measured in volts): :P = I ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
