Answer / sayyid ahamed pm

at the time of opening of cb more current and high voltages are causes to produce high arc due to air and moister are help to produce fire

Answer / mostafaghodrat

vaciuum c.b is advanced.

At the moment arc, and the keying is more effective.
air c.b is more expensive.

How to calculate electrical Induction motor heating and cooling time constant,11KV,2850,12P,SCIM

2 Answers   Bhel, Regal Beloit,

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what is power and what is watts detailed description and formulas

2 Answers  

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Is it necessary to seperate the DG earth grid with Electricity Board earth grid for protecting the DG set. if yes why?

2 Answers   BARC,

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why use phase displacement in transformer.and effect of phase displacement on transformer

0 Answers   IOCL, ONGC,

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What device is use for metering current at lt consumer end..??

2 Answers   Power Grid,

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What is the difference between expansion joints & thermal expansion joints in Bus bar

1 Answers  

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what is the difference in using the 125% and the 250% factor of safety in calculating circuit breakers capacity for motors,which is more reliable to use the 125% or 250%??

1 Answers  

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What are capacitive,resistive,inductive surge absorbation? What is ferranti surge absorber? What is lagrangian cost? What is Px operator?

0 Answers  

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in case dc we mark as + ve & -ve..but in case a.c. we mark as ph&N...Y LIKE PLZ TELL ME

4 Answers   NPTC, TCS,

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explain why tap changer is always connected to high voltage winding side of the transformer.

10 Answers   IOCL, UPPCL,

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i have need all detail above basic transformer question..

0 Answers  

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what are the electrical components required for run the motor pump including safety components plz explain it how we can use such components .

2 Answers  

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