Found 123 Articles for Utilisation of Electrical Power

DC Traction SystemA traction system in which DC series motors are used for running the electric trains is known as DC traction system. The DC power to be fed to DC series motor is obtained from substations which are located at a distance of 3 to 5 km for urban and suburban heavy traffic and 15 to 30 km for main line service.AC Traction SystemA traction system in which AC motors (1-phase or 3-phase induction motors) are used for running the electric trains is known as AC traction system.In AC traction system, a high voltage is fed to the overhead ... Read More

What are Traction Systems?The word "traction" means the action of pulling an object over a surface, especially a road or track. The action of propelling vehicles by electric power derived from overhead wires, third rail, storage batteries or diesel generators mounted on the vehicles is known as electric traction. In simple words, the traction system which uses electric power for its operation is known as electric traction.The electric traction system is widely used in electric trains, tramcars, trolley buses and hybrid vehicles, etc.Traction systems can either be electric or non-electric depending on the type of source from where they draw ... Read More

A compact fluorescent lamp (CFL) is a type of fluorescent lamp that has been compressed into the size of an ordinary incandescent lamp. It works on the principle of gas discharge, i.e., ionization of gas by the electric current.The modern CFL was invented by Edward E. Hammer in 1973.CFLs are the lamps of choice for those looking for an energy efficient alternative to incandescent lamps.CFLs consume very less power than an incandescent lamp.The increasing variety of shape and color and small size of CFL have made them more versatile and acceptable than the conventional long tube fluorescent lamps.Construction and Working ... Read More

Photometry and PhotometerThe measurement of light's brightness or luminous intensity is known as photometry. Photometry focuses on the perceived brightness to the human eyes. The photometry takes into account the eye's sensitivity to varying degrees of light and focuses primarily on the visible light spectrum.Thus, the photometry involves the measurement of candle power. The candle power of a given source of light in any given direction is measured by comparison with a standard source. In order to eliminate the errors in the measurement of the candle power, the measurement is performed in a dark room with dead black walls."The device ... Read More

A source of light that is mounted on a lamp column or pole either on the side of the road or within the median to provide illumination is known as street lighting.Street lighting is required along the road to have safer, comfortable, convenient and efficient movement of vehicles at night.Objective of Street LightingThe primary objectives of street lighting are −Street lighting is required to increase or enhance the community value of the street.Street lighting is provided along the road sides to make traffic and obstructions on the road clearly visible in order promote safety and convenience.Street lights also make the ... Read More

Spot WeldingThe welding process which is used for welding two or more metal sheets together by applying pressure and heat from an electric current to the weld area is known as spot welding.Spot welding is a type of resistance welding process, which is why it is also known as the resistance spot welding.Schematic DiagramThe figure below shows the schematic diagram of resistance spot welding −Spot welding is the simplest and most universally adopted method of making lap joints in thin sheet up to a maximum thickness of 12.7 mm.A typical spot welding machine consists of a transformer to produce high ... Read More

Seam WeldingThe welding process in which two similar or dissimilar materials are joined at the seam by the application of heat generated from electrical resistance is known as seam welding. The seam welding is a types of resistance welding, in which weld is produced by roller electrodes instead of tipped electrodes.Most seam welding processes produce a continuous or intermittent seam weld near the edge of two overlapped metals by using two machine driven roller electrodes. As in the seam welding process, the roller electrodes move over the metal workpieces, the workpieces are under pressure and the current passing through them ... Read More

Polar CurvesThe plots drawn between the candle power and angular position are known as polar curves. Due to unsymmetrical shape of the lamps, the luminous intensity is not uniform in all directions. The luminous intensity in all directions can be represented with the help of polar curves.The polar curves are drawn by taking the luminous intensities in various directions at an equal angular displacement in the sphere. A radial ordinate pointing in any particular direction on a polar curve represents the luminous intensity of the source when it is viewed from the direction.Therefore, the polar curves are classified into two ... Read More

Laser Beam Welding (LBW) is a fusion welding process in which multiple pieces of metal are joined together through the use of laser. In LBW, the laser beam acts as a concentrated source of heat, which allows narrow, deep welds and high welding rates. The laser beam welding process is frequently used in high volume applications, such as in the automotive industry.Laser Beam Welding ProcessThe figure shows the schematic diagram of the laser beam welding (LBW).The main parts of the set up used for the laser beam welding are as follows −Laser Machine – It is the machine that is ... Read More

The light received by any surface depends upon the angle made by the normal to the surface, to the light flux. The Lambert's cosine law of illumination explains the relation between the illumination of the surface and the cosine of the angle.StatementThe Lambert's cosine law of illumination states that"The illumination of a surface is directly proportional to the cosine of the angle between the normal to the surface and the direction of incident light".That is, $$\mathrm{\mathit{E}\propto cos\, \theta \: \: \: \cdot \cdot \cdot \left ( 1 \right )}$$ExplanationCase I – Consider a surface that is normal to the luminous ... Read More