ELECTRICAL ENCYCLOPEDIA

What is a Transistor? http://en.wikipedia.org/wiki/Transistor   A transistor is a semiconductor device used to amplify and switch electronic signals. It is composed of a semiconductor material with at least three terminals for connection to an external circuit. A voltage or current applied to one pair of the transistor's terminals changes the current flowing through another pair of terminals. Because the controlled (output) power can be much more than the controlling (input) power, a transistor can amplify a signal. Today, some transistors are packaged individually, but many more are found embedded in integrated circuits. continue..   History of a Transistor http://nobelprize.org/educational/physics/transistor/history/   The transistor is a three terminal, solid state electronic device. In a three terminal device we can control electric current or voltage between two of the terminals by applying an electric current or voltage to the third terminal. This three terminal character o

What is an Integrated Circuit? http://en.wikipedia.org/wiki/Integrated_circuit   An integrated circuit or monolithic integrated circuit (also referred to as IC, chip, or microchip) is an electronic circuit manufactured by the patterned diffusion of trace elements into the surface of a thin substrate of semiconductor material. Additional materials are deposited and patterned to form interconnections between semiconductor devices. Integrated circuits are used in virtually all electronic equipment today and have revolutionized the world of electronics. Computers, cell phones, and other digital appliances are now inextricable parts of the structure of modern societies, made possible by the low cost of production of integrated circuits. continue.. Basics of Integrated Circuit http://www.solarbotics.net/bftgu/starting_elect_ic.html   Integrated circuits (ICs) are, much as their name would suggest, small circuits integrated into a plastic "chip." They provide a handy source of ric

What is a Diode? http://en.wikipedia.org/wiki/Diode   In electronics, a diode is a two-terminal electronic component. A semiconductor diode, the most common type today, is a crystalline piece of semiconductor material connected to two electrical terminals. A vacuum tube diode (now little used except in some high-power technologies) is a vacuum tube with two electrodes: a plate and a cathode. The most common function of a diode is to allow an electric current to pass in one direction (called the diode's forward direction), while blocking current in the opposite direction (the reverse direction). Thus, the diode can be thought of as an electronic version of a check valve. This unidirectional behavior is called rectification, and is used to convert alternating current to direct current, and to extract modulation from radio signals in radio receivers. continue.. Diodes and Rectifiers http://www.allaboutcircuits.com/vol_3/chpt_3/1.html   A diode is an electrical device allowing curren

True, Reactive, and Apparent Power http://www.allaboutcircuits.com/vol_2/chpt_11/2.html   We know that reactive loads such as inductors and capacitors dissipate zero power, yet the fact that they drop voltage and draw current gives the deceptive impression that they actually do dissipate power. This “phantom power” is called reactive power, and it is measured in a unit called Volt-Amps-Reactive (VAR), rather than watts. The mathematical symbol for reactive power is (unfortunately) the capital letter Q. The actual amount of power being used, or dissipated, in a circuit is called true power, and it is measured in watts (symbolized by the capital letter P, as always). continue.. Power Factor Triangle http://www.the-power-factor-site.com/Power-Factor-Triangle.html   Vectors are simply another way to draw sine waves. You'll see its not difficult and actually makes things easier. Vectors, as used in this discussion, are representations of a sine wave of current relative to a sine wave

Worlds Largest 3-Phase Motor http://www.phaseable.com/   The revolutionary motor system shown here uses a PhaseAble® circuit that connects a low-cost three-phase motor to a Single-Phase supply to make a high-performance single-phase motor system. The patented Smith PhaseAble® Enabler® has a single-phase 2-pole circuit breaker, line contactor, start contactor, start capacitor bank, and run capacitor bank. This injects currents into the motor windings so that the motor has the same full-load high efficiency from a single-phase supply that it would have on a balanced 3-phase supply :. continue.. How to make the simplest electric motor? http://www.evilmadscientist.com/article.php/HomopolarMotor   The most common type of electric motor is the brushed dc electric motor. This is the kind that you'll find inside essentially everything that moves (or shakes) and runs on batteries. This type of motor attracts an electromagnet towards a permanent magnet. When the two are close enough,the p

What is a Synchronous Motor? http://en.wikipedia.org/wiki/Synchronous_motor   A synchronous electric motor is an AC motor distinguished by a rotor spinning with coils passing magnets at the same rate as the power supply frequency and resulting rotating magnetic field which drives it. Another way of saying this is that it does not rely on slip under usual operating conditions and as a result, produces torque at synchronous speed. Synchronous motors can be contrasted with an induction motor, which must slip in order to produce torque. They operate synchronously with line frequency. As with squirrel-cage induction motors, speed is determined by the number of pairs of poles and the line frequency. continue.. Synchronoue Motors Application and Operation http://www.engineersedge.com/motors/synchronous_motor.htm   A synchronous electric motor is like an induction motors in that they both have stator windings that produces a rotating magnetic field. Unlike an induction motor, the synchrono

What is an Induction Motor? http://en.wikipedia.org/wiki/Induction_motor   An induction or asynchronous motor is a type of AC motor where power is supplied to the rotor by means of electromagnetic induction, rather than by slip rings and commutators as in slip-ring AC motors. These are widely used in industrial drives, particularly polyphase induction motors,[citation needed] because they are robust, have no friction caused by brushes, and can have the speed of the motor controlled easily.. continue.. Single Phase Induction Motor http://www.allaboutcircuits.com/vol_2/chpt_13/9.html   Single-phase induction motors are not self-starting without an auxiliary stator winding driven by an out of phase current of near 90o. Once started the auxiliary winding is optional. The auxiliary winding of a permanent-split capacitor motor has a capacitor in series with it during starting and running. A capacitor-start induction motoronly has a capacitor in series with the auxiliary winding during star