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Showing posts from February, 2021

Theory of Star Delta Starter Method

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  Star Delta Starter The  Star Delta Starter  is a very common type of starter and is used extensively as compared to the other type of starting methods of the induction motor. A star delta is used for a cage motor designed to run normally on the delta connected stator winding. The connection of a three-phase induction motor with a star delta starter is shown in the figure below. When the switch S is in the  START  position, the stator windings are connected in the star as shown below. When the motor picks up the speed, about 80 percent of its rated speed, the switch S is immediately put into the  RUN  position. As a result, a stator winding which was in star connection is changed into  DELTA  connection now. The delta connection of the stator winding in shown in the figure below. Firstly, the stator winding is connected in star and then in Delta so that the starting line current of the motor is reduced to one-third as compared to the starting current with the windings connected in del

Difference Between AC & DC Voltage

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  The major difference between the AC and DC voltage is that in AC voltage the polarity of the wave changes with the time whereas the polarity of the DC voltage always remains same. The other differences between the AC and DC voltage are shown below in the comparison chart. Content: AC Voltage Vs DC Voltage Comparison Chart Definition Key Differences Comparison Chart Basis for Comparison AC Voltage DC Voltage Definition The AC voltage is the force that derive the alternating current between the two points. The DC Voltage induces the direct current between the two points. Symbolic Representation Frequency Depends on country. Zero Power Factor Lies between 0 to 1. 0 Polarity Changes Remain Constant Direction Vary Remain same Obtained From Generator Cell or Battery Efficiency High Low Passive Parameter Impedance Resistance Amplitude Have Don't Have Conversion By using inverter. By using rectifier. Transformer Requires for transmission. Not requires. Phase and Neutral Have Don't Ha

Difference Between Alternating Current (AC) & Direct Current (DC)

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  The conducting materials have free electrons which move from one atom to another when the potential difference is applied across them. This flow of electrons in a closed circuit is called current. On the basis of the direction of movement of electrons in a closed circuit, the electric current is mainly classified into two types, i.e., the alternating current and the direct current. One of the major differences between the alternating and direct current is that in alternating current the polarity and the magnitude of the current changes at the regular interval of time whereas in direct current it remains constants. Some of the differences are explained below in the form of the comparison chart by considering the various factors; Content: Alternating Current (AC) Vs Direct Current (DC) Comparison Chart Definition Key Differences Point to Remember Comparison Chart Basis Alternating current Direct current Definition The direction of the current reverse periodically. The direction of the