Answer / naveen

SF6 is like VCB except arcing medium is Sulfer hexa fluride gas which is very good non conductive properties & reduces the arc flash it has all the safty relay I.e- over current.earth fault.sensitive earth fault transformer safty relays master trip relay tcs relay.

when i am going to take trail on a 3ph sq.i/m motor 5.5kw, i observed that RPM of the motor is very low as compared to the rated RPM and also it rotates in clockwise in first ON command,and anticlock wise in second ON command. finally i observed that on phase is no available . but iam not clear about, why the motor is rotates in both directions without any phase interchanging.pls answer to my question.

1 Answers  

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improve power factor by : 1)shunt reactor 2)shunt capacitor 3)series capacitor 4)series reactor

2 Answers  

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What are the basic & Majour problems in UPS ?

0 Answers   Roto Power, RotoPower,

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Is it possible to measure correct value of earth resistance & cable insulation ristance with out disconncting earth lead & both sides of cable ends? If not, any other method to measure ER & CIR with out disconneting from the system.

0 Answers   HAL,

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why do we use 25kv supply for traction purpose

1 Answers  

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how much insulation resistance 11kv & 33kv under ground cable between earth to phase & phase to phase.

4 Answers   Siemens,

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What happens if i apply 500V to 440V rotary Switch ?

0 Answers  

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Why neutral shows voltage with earth ?

2 Answers   MRF,

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WHY DOES NEUTRAL DO NOT CARRY EVEN THOUGH IT CARRIES RETURN CURRENT?

3 Answers  

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In response to Mr Bikas. If fault current is 52 kA then what will be the CT specification

1 Answers  

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for a slip ring induction motor if the stator is short circuited and rotor is given supply? how does the rotor rotate?

1 Answers   TNEB Tamil Nadu Electricity Board,

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Difference between SFU & FSU with advantantages & drawback?

1 Answers  

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