ADVANTAGES OF AUTO TRANSFORMER STARTER: a ) On the 65% tapping the line current is approximately equal tp that of a Star-Delta starter, however, at the time of switching from reduced voltage to the full supply voltage, the motor is not disconnected so that the second peak is very much
ADVANTAGES OF STAR DELTA STARTER: a ) Star-Delta starters are widely used due to their relatively low price. b ) There are no limits to the number of times they can be operated. c ) The components require very little space. d ) The starting current is reduced to approximately
Whenever possible a squirrel cage three-phase motor should be started direct-on-line ( D.O.L. ) by means of contactors. It must be taken into account that for a certain motor the torque and current values are fixed, irrespective the load, for a constant voltage. In cases where the motor starting current
Considering that an induction motor is a simple designed and rugged construction machine, its life time will exclusively depend on the quality level of the insulation materials. Motor insulation is affected by several factors including moisture, vibration, corrosive environments and others. Among all these factors, operating temperature of the insulating
The electric motor is a machine capable of converting electrical energy into mechanical energy. The induction motor is the most widely used type of motor, because it combines all the advantages offered by the electrical energy such as low cost, easy of supply and distribution, clean handling and simple controls
A single prime mover – generator and substation No need for electric transmission connection to the wind farm (only to the Expandera-generator), Wind turbine gear box requirements are greatly simplified (since the speed/torque characteristics of a wind turbine rotor are better matched to an air compressor than a generator). No
Using the sun to dry crops and grain is one of the oldest and most widely used applications of solar energy. The simplest and least expensive technique is to allow crops to dry naturally in the field, or to spread grain and fruit out in the sun after harvesting. The
Solar stills are systems designed to filter or purify water. The number of systems designed to filter water have increased dramatically in recent years. As water supplies have increased in salinity, have been contaminated, or have experienced periods of contamination, people have lost trust in their drinking water supply. Water
Solar Thermal power is heat energy obtained by exposing a collecting device to the rays of the sun. A solar thermal system makes use of the warmth absorbed by the collector to heat water or another working fluid, or to make steam. Hot water is used in homes or commercial
Photovoltaic are solar cells that produce electricity directly from sunlight. The solar cells are made of thin layers of material, usually silicon. The layers, after treatment with special compounds, have either too many or too few electrons. When light strikes a sandwich of the different layers, electrons start flowing and
