Answer / renish2905

Becuse of the fault current is very large and small time about 1 second or friction of second.in this time CB is activated nearly less than of second.and all about calcualtion to took fault current time 1sec for easy to calculation.

Answer / asivasankar2k

As per my view, All equipment made to withstand 1sec only

Answer / adnan

Fault current is too large, about 7 times the normal current. If this current flows for longer time, it will burn all the equipments. So, breakers are designed to operate in 0.3 sec, 0.5 sec time if fault is not cleared in this time.
So such large current, even 1 sec is too long time.

The sodium vapor lamp is not glows when it is connected a distance of 5 meters above from gearbox, why ?

0 Answers   Ispat,

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During the main stator winding insulation testing (phase to ground)of 11kv alternator (Lerysomer) i found 0 and resistance with multimeter and found 20 killo ohm while the power cables are connected both end (Generator & VCB). In VCB PT (Potential transformer) are connected. Please any body explain that method of insulation is correct or not? also describe of PT connections

1 Answers   Private,

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what is the speed of the darkness?

3 Answers   Wipro,

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What are the advantages and disadvantages of the ac motors?

0 Answers  

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what is encoder & its use?

1 Answers   ACC,

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the rating of fuse wire i always expressed in what?

3 Answers  

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How does CT can measure the high value DC current?

4 Answers  

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what happen if rotor earth fault in AVR system?

1 Answers  

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kVA rating of ordinary transformer is increased when connected as an auto transformer because A transformation ratio increased B secondary voltage increased C energy is transferred both inductively and conductively D secondary current increased

0 Answers  

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how to find impedance , mutual indatnce in transmission lines

0 Answers   NTPC,

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Any one can explaination about calibration with rotating sub standards?

0 Answers  

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I have a drawing of a wound rotor induction motor for a crane. This crane motor has 5 forward speeds & 5 reverse speed implemented of course with different amount of resistance for each speed setting selected. What has got me scratching around is the fact that 8 of the 10 speed selections switch in uneven (unbalanced) amounts of resistances on each of the 3 connections to the motor's rotor.Can this be possible? I would have assumed this would produce unbalanced rotor currents and therefore vibration in the motor. I would greatly appreciate anyone's comments on this. Many thanks, Confused.

0 Answers  

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