In DC while we mention the voltage we are using -48V but in case of AC we mention only 230V not -230V, why we using -48V not 48V

2 Answers  

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why we step down the voltage from 440 to 220 in machines

4 Answers  

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what is the difference between changer, converter and transformer?

0 Answers  

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Which thing is maximum in RLC circuit at resonance a)power consumption b)inductive current c)capacitive voltage

0 Answers  

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what is power frequency withstand and impulse withstand of a circuit breaker?

2 Answers   Power Grid,

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What does the letter CTNM in negative phase sequence relay means?

0 Answers  

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In a d.c circuit, if current and resistance are known, power (P=I*I*R) can be determined. This relationship also applied to an a.c circuit. Comment the reason for this.

3 Answers  

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what is the distance between two overhead lines

1 Answers   Aurobindo,

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How can we decide cable size from HT panel to Transformer? Please give you reply with some examples.

0 Answers  

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What is the relation between the Peripheral speed(N) , no.of poles(P) and diameter(D) of a cylindrical rotor alternator ?

5 Answers   NTPC,

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if the field circuit of a d.c. shunt motor running without load gets opened, then the motor will

3 Answers  

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what is the surge arrestor?how it operates?what is the range for it?

4 Answers  

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