Answer / ashraf nasr

mcb ' miniture circuit breaker' installed at the final
distribution circuits - as close as can be to loads - in
order to protect loads

mccb ' molded case cicruit breaker' used as a main breaker
for branches . it has higher rupture capacity

acb 'air circuit breaker' used as a main breaker for the
whole network - on the head of the transformer- since it
provide releabilty for its slow opertaion

vcb ' vaccum circuit breaker' it only differs due to the
damping meduie and its used in distributors

what should be the minimum rating for using HT Motors?

1 Answers   BSL,

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how one can know the charging time, discharging time of a 12 VDC battery ? If i have a battery of 12 VDC , 4.0 AH , how long will it take to charge from a charger (power supply) of input 220 V , Output 15 V and output current of 3000 mA and how long will it take to discharge whether using or not ? How much backup will it give ?

1 Answers   ONGC,

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What about Reactive power.and role of that one?

7 Answers  

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While converting delta into star or star into delta ,the three values of resistances remains unchanged .Find out the value?Let In star R1=x;r2=x;R3=x On converting into delta,R12=x;R23=x;R31=x Find the value of x

0 Answers  

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what is the IS foe lightning arrester?

0 Answers  

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why rotor winding in induction motor is not earthed. normally we uses star winding in rotor .why?

3 Answers   Anglo Platinum, TATA,

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Wht is the meaning of floating neutral

9 Answers   Cipla,

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Why earthing transformer used in Distribution Sub-Station?

3 Answers  

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what mean ohm

1 Answers   Shoba Devlopers,

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MCB Rating

1 Answers  

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what is earth resistance? how to measured? and give values at power station and mcc area?

0 Answers   Essar,

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what is difference b/t ac current and dc current

4 Answers   L&T, Meghana Engineers,

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