Found 177 Articles for Power Systems

A metal halide lamp, also called mercury halide lamp, is an electric lamp that produces light by an electric arc through a gaseous mixture vaporized mercury and metal halides. The metal halide lamp was invented by Dr. Reiling in 1960.Construction of Metal Halide LampThe construction of a metal halide lamp is shown in the figure below −A metal halide lamp consists of a metal base and a glass shield to protect the internal components of the lamp. Inside the glass shield, there is a series of lamps combined within a single arc tube with output characteristics of different mixtures of ... Read More

The combination of an electric motor, energy transmitting shaft and control devices for motion control is known as electric drive. The following figure shows the block diagram of a typical electric drive.Based on their assembly, electric drives are classified into the following categories −Individual DriveGroup DriveMulti-motor driveGroup driveWhen several machines are organized on a single shaft and are driven by a single large motor, this system is known as group drive. Group drive is also known as line shaft drive because a large sized motor (called main motor) drives a common shaft. To the common shaft, a number of small ... Read More

IlluminationWhen light falls on a surface, the surface is illuminated and the phenomenon is known as illumination. Mathematically, the illumination is defined as the luminous flux falling on a surface per unit area, i.e., $$\mathrm{\mathrm{Illumination, }\mathit{E}\:=\:\frac{\mathrm{Luminous \:flux}}{\mathrm{Area}}}$$Good Illumination SchemeA good illumination scheme is the one under the influence of which the eyes of a person, using the light, do not feel any strain.For example, if the light is too dim, then one cannot observe the objects properly. On the other hand, if the light is too bright, then eyes start watering and are made to open forcibly. Thus, the good ... Read More

Welding is a skilled work and at the same time it is risky and requires safety equipment and accessories to safeguard the welder. Welders use various types of welding equipment accessories for protection and safety, which we are going to explain in this article.Welding GlovesThe gloves are used for the protection of the welder’s hands and arms.The material used for making the gloves is a good quality thick rubber which is more flexible for hand movements.There are two types of gloves used in welding work viz.: Gauntlet type gloves and Tig type gloves.Tig type gloves are of high weight and ... Read More

A type of electric lamp that produces light by creating an electric arc in the gap between two electrodes when the electric supply is connected to these electrodes is known as arc lamp.Types of Arc LampsArc lamps are classified into following four types, viz −DC Carbon Arc LampAC Carbon Arc LampFlame Arc LampMagnetic Arc LampDC Carbon Arc LampThe construction of the DC carbon arc lamp is shown in Figure-1.In this types of carbon arc lamp, two carbon electrodes are used. These two electrodes are placed touching to each other face to face and a DC supply of voltage of 40 ... Read More

A tungsten halogen lamp, also called halogen lamp, is a developed tungsten filament lamp. The halogen lamp consists of a tungsten filament that is enclosed in an environment of an inert gas and a small quantity of a halogen such as bromine or iodine.The combination of the tungsten filament and halogen results in a chemical reaction known as halogen cycle, which increases the life of the filament and eliminates the drawbacks of an ordinary filament lamp.The halogen lamp was developed by E. G. Fridrich and E. H. Wiley in 1958 by introducing a halogen gas inside the incandescent lamp. The ... Read More

Welding is the process of joining two metals placed together by heating them to melting point. In electric welding, the heat required for welding process is obtained by the use of electrical energy.Factors Considered While Selecting a Welding System for a Particular JobThere are different materials or metals to be welded and different types of welds are required. Therefore, depending upon the metal, its dimensions, and requirements, different welding systems are selected.The following factors are to be considered while evaluating an appropriate welding system to complete a specific job −Types of material (or metal) being weldedThickness of the material.The welding ... Read More

There are various types of electric lamps available in the market. The selection of a lamp depends upon the illumination area.Selection Criteria of Different Electric LampsThe following table highlights the points that you should consider while selecting a lamp depending upon the area to be illuminated.Illumination AreaSuitable Lamp / LampsGeneral house illuminationIncandescent lampsFluorescent lampsCFL (Compact fluorescent lamps)LED (Light Emitting Diode Lamps)Street lightingFluorescent tube lampsSodium vapor lampsMercury vapor lampsLEDsOutdoor lighting of a buildingHalogen lampsLEDsIndustrial lightingHigh pressure mercury vapor lampsMercury iodide lampsCommercial places (like shopping malls)High pressure mercury vapor lampsGreen lightingFluorescent tube lampsLEDsLarge gardensMercury vapor lampsHalogen lampsSodium vapor lampsDecoration of buildingsNeon tube ... Read More

A miniature gas discharge lamp in which the electrical discharge takes place through a mixture of gases containing a large proportion of neon gas is known as neon lamp.The working principle of the neon lamp is as follows −“Electrons are emitted from cathode by subjecting the surface of the cathode to very high electric voltage so that the electrons are forcibly ejected from the orbits of the atoms against the nuclear centripetal forces.”Construction of Neon LampThe construction of a typical neon lamp is shown in the figure.The neon lamp has two closely spaced electrodes, but not touching each other, in ... Read More

Types of Railway Services (Classification of Traction Services)Railways offer the following three types of the passenger traction services viz −City or Urban ServiceSuburban ServiceMain Line ServiceCity or Urban Railway ServiceIn the city or urban railway service, there are frequent stops, the distance between these stops being nearly 1 km or less. Therefore, in order to obtain moderately high schedule speed between the stations, it is essential to have high acceleration and retardation.Suburban Railway ServiceIn case suburban railway service, the average distance between the stops ranges from 3 km to 5 km. The suburban railway services require rapid acceleration and retardation ... Read More