Deepakkumar Yadav
State the functions of protective system. As mentioned above, protective system should operate automatically under abnormal condition within minimum time. Apart from this it should have following essential features : Quick operation : To minimize the damage to the faulty part, the switchgear must operate as quickly as possible after the occurrence of fault If … Read more
Flame – Arc Lamp : Working principle : Two carbon rods kept face to face touching to each other connected to the source of electricity and if they are departed from each other to form a small air gap between them, an arc is produced with tremendous heat and a light is produced. The principle … Read more
A.C. carbon arc lamp : Working principle : Two carbon rods kept face to face touching to each other connected to the source of electricity and if they are departed from each other to form a small air gap between them, an arc is produced with tremendous heat and a light is produced. Construction and … Read more
Carbon Arc Lamps : Working principle : Two carbon rods kept face to face touching to each other connected to the source of electricity and if they are departed from each other to form a small air gap between them, an arc is produced with tremendous heat and a light is produced. (a) D.C. carbon … Read more
Gas Filled Incandescent Lamp : Construction : Construction is same as vacuum lamps. Working : A metal filament can work in an evacuated bulb upto 2,000°C without oxidation and if it is worked beyond this temperature it vaporizes quickly and blackens the lamp. For higher efficiency it is necessary to use … Read more
Types of Lamps : There are various types of lamps used in lighting (illumination system). The lamps can be listed as below :(1) Incandescent lamp : (a) Vacuum lamps (Filament lamp) (b) Gas filled incandescent lamp (2) Arc lamps : (a) D.C. Carbon arc lamp. (b) A.C. carbon … Read more
Extra High Voltage Direct Current Transmission System A high-voltage, direct current (HVDC) electric power transmission system uses direct current for the bulk transmission of electrical power. The above figure shows the simple block diagram of HVDC system. Generated voltage is stepped up with the help of step up transformer and then converted in to DC … Read more
Incandescent Lamp (a) Vacuum Lamps / Filament Lamps : These lamps can operate upto the temperature of 2000°C. The construction is shown in the Figure (A) The filaments used for this type of lamp are carbon, osmium, tantalum or tungsten. Tungsten is best of all. The filament materials have the properties: High melting point. Low … Read more
HRC Fuse (High Rupturing Capacity Fuse) HRC means “High Rupture Capacity”. The rupture capacity is the maximum current that can safely be interrupted by the fuse. A fuse is designed to melt and break the circuit if a preset “trip current” is exceeded. However, most fuses not designated HRC can only reliably break up to … Read more
Explain importance and purpose of earthing. To save human life from shock due to current leakage of installation. To protect large buildings from lightening fall. To isolate the faulty, section. This is achieved by providing path of leakage current through earthing system at this instant protective gearing operates. To protect installed machines fed from O.H. … Read more