Electrical engineering

TWO-WAY LIGHTING CIRCUIT                                                      A lighting circuit is often used on staircases so that one can switch off the downstairslight from upstairs, or vice versa.    In this circuit, the switches can have two positions, either of which can light the lamp. Suppose switch 1 is in the upper position, and switch 2 is in the lower position, as illustrated, there is no circuit, so the lamp is out. If switch 2 is operated a circuit is established, and the lamp lights. Now if switch 1 is operated the lamp goes out. The two wires between switches 1 and 2 are called ’strappers’. Intermediate lighting circuit When it is required to control the lighting in a long corridor or staircase with several landings, it is desirable to arrange for lights to be switched on and off at several point...

A  battery  is a device consisting of one or more electrochemical cells with external connections for powering electrical devices such as flashlights, mobile phones, and electric cars. When a  battery  is supplying electric power, its positive terminal is the cathode and its negative terminal is the anode. Batteries  are widely  used as  sources of  direct-current  electrical  energy  in automobiles, boats, aircraft, ships, portable  electric/electronic  equipment, and  lighting  equipment. In  some  instances, they  are used as the only  source of  power;  while  in others,  they  are used as  a secondary  or standby  power source.                                         A battery  consists of  a number of  cells assembled...

Fuse  is an electrical device.it used for purpose of protective our electrical circuit or electrical device against over current or harmful current. Resistance of Fuse wire :                                     Fuse  has low  resistance  with comparison to the load  resistance  of the circuit but has high  resistance  when compared to the  wire  of same length. Thus when asked weather a  fuse  has high  resistance  or low  resistance , we should answer that a  fuse  has high  resistance  with low melting point. How do fuses work? A  fuse  is exactly the same. It's a thin piece of wire designed to carry a limited electrical current. If you try to pass a higher current through the wire, it'll heat up so much that it burns or melts. When it melts, it breaks the circuit it's fitted to an...

Electrical Load Definition:         The device which takes electrical energy is known as the electric load. In other words, the electrical load is a device that consumes electrical energy in the form of the current and transforms it into other forms like heat, light, work, etc. The electrical load may be resistive, inductive, capacitive or some combination between them. The term load is used in the number of ways. Three basic types of loads exist in circuits: capacitive loads, inductive loads and resistive loads. These differ in how they consume power in an alternating current (AC) setup. Capacitive, inductive and resistive load types correspond loosely to lighting, mechanical and heating loads. Some scholars and engineers refer to "linear" and "nonlinear" loads, but these terms are not as useful. Resistive Loads Loads consisting of any heating element are classified as resistive loads. These include incandescent lights, toasters, ovens, ...

LED is an optical semiconductor device that converts electrical energy into light energy.  Also known as light emitting diode. And it also varies in different colors.       A semiconductor diode that emits light when current flow through it. When electrons in semiconductor recombine with electron wholes than an energy release in form of photon. Light emitting diodes emit either visible light or invisible infrared light when forward biased. The LEDs which emit invisible infrared light are used for remote controls.   LEDs A diagram of the inside of an LED is shown in Figure  The chip at the heart of the LED consists of a p-n junction --- two different solid materials that have been joined together. It is surrounded by a transparent, hard plastic that protects the LED from vibration and shock. The LED is constructed in such a way that the light emitted by the chip is reflected off the base it sits on and i...

Capacitor is an electrical component in which we store Electrical energy electric field. A capacitor behavior like a battery for little bit time. It's unit is FARAD, and it represented by F. It consists of two parallel plates separated by an insulating material called the dielectric • In the neutral state, both plates have an equal  number of free electrons • When a voltage source is connected to the  capacitor, electrons are removed from one plate and an equal number are deposited on the other plate • No electrons flow through the dielectric (insulator) Capacitance of capacitor : The capacitance of a capacitor -- how many farads it has -- depends on how it's constructed. More capacitance requires a larger capacitor. Plates with more overlapping surface area provide more capacitance, while more distance between the plates means less capacitance. The material of the dielectric even has an effect on how many farads a cap has. The total c...

It's Electronic device in which we measure current in amperes (A)in close Circuit. It is connected in series with circuit. The effective resistance of ammeter is low The Resistance of an ammeter is zero. A moving coil of galvanometer is converted in to an ammeter by connected a suitable low resistance in parallel to it. Circuit must be disconnected in order to attach the ammeter. Ammeter considered as less accurate value. Type of ammeter There are 7 type of ammeter. 1.Moving coil  2-Moving magnet  3-Electrodynamic  4-Moving iron  5-Hot wire  6-Digital  7-Integrating Moving coil ammeter:                                   The D'Arsonval galvanometer is a moving coil ammeter. It uses magnetic deflection, where current passing through a coil causes the coil to move in a magnetic field. The modern form of this instrument was devel...