Answer / biren

In overhead line there is air around the bare conductor which is a insulation layer but the earth around the under ground cable is a good conductor. so there is more chance of insulation failure, hence to avoid the normal insulation failure more insulation is provided which increases the cost.

Answer / sk.azhar.m

An underground line is fill in the earth and when if the leakage current will flo in the erth the current rating will very high in the cable that is very dangerous for human and other and in the the overhead line the air is not good conductor of electricity while an underground line is more insulation than overhead line for this reason the insulation cost is more in underground system

what r the earthing required for commissioning of D.G set?

5 Answers  

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why transformer comes only in standard rating like 11kv,33kv,66kv....and not like 33.33kv and so on?

3 Answers  

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What do you understand by oldham's coupling ?

0 Answers   Godrej,

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Why the standard of ambient teperature mentioned as 40 degree celcius in machines.

0 Answers  

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what is the purpose of slope in the differential relay?why we are using two slope?but in busbar differential we are using only one slope.why?

0 Answers  

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How will be the single line diagram of series trip HT breaker? how it works?

0 Answers   HAL,

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why we use 25 kv in railway .not 11kv, or 33 kv

2 Answers   ISRO,

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what is the back ground of transformer working? applying voltage to primary and emf inducing in primary and secondary? how it is possible? please answer me with scientific approach?

5 Answers  

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What is the RME and explain the full form and what is the RME work?

0 Answers   JLL,

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What is load shedding?

1 Answers  

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We have 800KW motor operating at 6600Volt,50 Hz supply.During 1st startup it tripped on overcurrent trip.It's FLA is 88 Amps.The K factor of Thermal overloaaad was set on .94 initially.then we set at 0.97 and then it started fine.i dont understand why it tripped first?What are the protections which comes in picture during starting ?

6 Answers  

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what is the responsibilities of electrical project engineer?

2 Answers  

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