Found 158 Articles for Electrical Engineering

Good Lighting SchemeA good lighting scheme is the one under the influence of which the eyes of a person do not feel any strain. For example, if the light is too dim, then we cannot observe the objects properly or cannot do reading or writing work. On the other hand, if the light is too bright, then our eyes start watering and are made to open forcibly. However, the good lighting does not have the above mentioned effects, but we find comfort while working under it.Requirements of Good Lighting SchemeIn order to make a lighting scheme good, the following factors ... Read More

IlluminationThe luminous flux received by the surface per unit area is known as illumination. It is denoted by the letter 'E' and is measured in Lux or Lumen/m2.Mathematically, the illumination is given by the expression, $$\mathrm{Illumination, \mathit{E}\: =\: \frac{Luminous \: Flux\left ( \phi \right )}{Area \left (\mathit{A} \right )}\: =\:\frac{\mathit{C\, P}\times \omega }{\mathit{A}}}$$Luminous IntensityLuminous intensity is defined as the amount of luminous flux emitted into a solid angle of a space in a specified direction. It is denoted by 'I' and is measured in Candela.Mathematically, $$\mathrm{Luminous\:Intensity, \mathit{I}\: =\: \frac{Luminous \: Flux}{Solid \: angle}}$$BrightnessThe luminous intensity per unit surface area of ... Read More

Projection welding is the resistance welding process which joins the metal pieces together by using the heat generated by an electric current. In this welding process, different projections are formed on the workpieces for effective welding, which is why the name "projection welding."Projection welding does not use electrodes for concentration of heat, instead the projection on the workpiece is used for this purpose. Actually, projection welding is a modified version of spot welding. It consists of forming slight projections on one of metal.Working of Projection WeldingThe schematic diagram of projection welding is shown in the figure.The set up used for ... Read More

Electrolysis is a process which uses the electric current to stimulate a non-spontaneous chemical reaction. Michael Faraday formulated two laws governing the electrolytic processes in 1833. These laws show the quantitative relationship between the substance deposited at the electrodes and the quantity of electric charge passed.Faraday's First Law of ElectrolysisFaraday's first law of electrolysis states that “the mass of substance deposited at any electrode in a given time is directly proportional to the quantity of electric charge passing through the electrolyte.”Mathematically, $$\mathrm{\mathit{m}\propto \mathit{Q}\:\:\:\cdot \cdot \cdot \mathrm{\left ( \mathrm{1} \right )}}$$$$\mathrm{\Rightarrow \mathit{m}\propto \mathit{It}\:\:\:\cdot \cdot \cdot \mathrm{\left ( \mathrm{2} \right )}}$$$$\mathrm{\therefore \mathit{m}\:=\: ... Read More

What is Illumination?The luminous flux received by the surface per unit area is known as illumination. It is denoted by letter 'E' and is measured in Lux. Mathematically, illumination is given by, $$\mathrm{\mathit{E}\:=\:\frac{\mathrm{Luminous\: flux}}{Area}}$$In this article, let's check some of the definitions related to illumination.BrightnessThe luminous intensity per unit surface are of the projected surface in the given direction is termed as brightness of that surface. It is denoted by the letter 'L' and measured in candela/m2.Mathematically, if the luminous intensity of the source is 'I' candela on area 'A'. Then, the projected area will be Acosθ. Therefore, the brightness ... Read More

What is Illumination?The luminous flux received by the surface per unit area is known as illumination. Illumination is denoted by the letter ‘E’ and is measured in lux or lumen per square meter or meter candela or foot candela.Mathematically, illumination is given by the formula, $$\mathrm{\mathit{E}\:=\:\frac{\mathrm{Luminous\:Flux}}{\mathrm{Area}}}$$Practically, the illumination deals with the selection, design, installation and maintenance of the artificial sources of light used in practice.In this article, let's make sense of some of the common terms used in illumination.Color & WavelengthThe energy radiation of the heated body is of one color (or monochromatic), that means, the radiation of only one ... Read More

For a commercial lighting design to be successful, each area of the building must have a sufficient level of light to allow users to perform their tasks. Thus, to determine the desired illumination, proper lighting calculations are to be made.There are a number of methods employed for lighting calculations, the three main methods are given as follows −Watt per Square Meter MethodLumen MethodPoint to Point MethodWatt per Square Meter MethodThe watt per square meter method is fundamentally a rule of thumb method. This method of lighting calculation comes in handy when doing a quick calculation or double-check. It entails allocating ... Read More

The filament is the most important part of an incandescent lamp. The life of the incandescent lamp depends upon its filament. The ideal material used for the filament of the incandescent lamps is the one which has the following properties −It should have high melting point.Low temperature coefficient.High resistivity.Low vapor pressure.It should be ductile.It should have sufficient mechanical strength to withstand the vibrations during the operation.Low thermal coefficient of expansion.Materials Used in Lamp FilamentDifferent types of materials are used for making the filament of an incandescent lamp, some of these materials along with their properties are described below −CarbonCarbon may ... Read More

Electroslag welding (ESW) is a high productive and single pass welding process, in which the heat required for welding is generated by passing an electric current between the consumable electrode and the workpiece through a molten slag covering the weld surface.The Electroslag welding process is mainly used for welding of thick (more than 25 mm to about 300 mm) materials in a vertical or close to vertical position.Process of Electroslag WeldingIn Electroslag welding, the electric arc is initially struck by a wire that is fed into the desired weld location and then welding flux is added. Some additional welding flux ... Read More

Electro Gas Welding (EGW) is continuous arc welding process in which an electric arc is struck between a consumable electrode and the workpiece. The electro gas welding was developed in 1961. It is a vertical position arc welding process. In case of electro gas welding, a shielding gas is sometimes used, but pressure is not applied.Electro gas welding is mainly used to make square groove welds for butt and t-joints.Equipment Used in Electro Gas WeldingThe electro gas welding process uses a constant voltage DC welding power supply. The voltage ranges from 30 V to 50 V, while the welding current ... Read More