Answer / pillay

drives are usually the motor that drives the machine. if the
motor is DC operated than it is a dc drive like wise if the
motor is AC than it is a AC drive.For ac motors vfds are
commonly used for speed control.

How to calculate cable sizing

5 Answers  

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what is the difference in MCB, MCCB, RCCB, ELCB, & MPCB (motor protection circuit bracker)

12 Answers   Afcons, Bhel, CIHSR, DCS, IOCL, L&T, Lupin, Siemens,

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can we start mulitple 3 phase induction motors with common starter?

1 Answers  

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How to calculate HT XLPE CABLE for 11 kv / 433 v , 1500 kva oil type transformer system? plz provide step by step calculation

15 Answers   Engineers India, Indian Railways, Polycab, Shashwat, Sitara Energy, Sonali Bank,

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Could Please Explain briefly. Why used stabilizing resistance series with High impedance bus differential protection relay.

0 Answers   NCC,

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how the transmission voltage ranges are decided like 11kV,33kV,66kV,132kV,220kV,400kV,725kV.... why not choose the transmission line voltage as 23kV,164kV,440kV?? what's the reason??

3 Answers  

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I am getting above 60 V as open delta voltage against single phase unit ICT at tertiary delta formed and ICT getting trippped on NDR. ICT tested and found in order. PTs provided on tertiary are tested and in order. what may be the reason?

0 Answers  

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what is subtransient , transient and study state ac components

2 Answers  

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What do you mean by cogeneration? What its working principle?

0 Answers  

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What is the formula to calculate the rating of a three phase miniature circuit breaker

0 Answers  

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We have 11kV/110V three phase indoor potential transformer in 66/11kV Sub-station, where the failure of PT is frequently happening and the rating of the PT is 0.2 class accuracy, with primary star and seconday (two cores) star connected. Some experts has suggested to not to connect the PT Primary neutral to the ground because when transformer neutal NCT connection is loose; the faulty current will flow through the PT primary neutral, resulting into failure of PT. My question is: Is it necessary to remove the primary neutral connection of the PT from ground? if not, what would be the reason for failure of PT. Please guide me.

2 Answers   KPTCL,

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1) Explain why we don't link the two earthing system ht and mv on a pole mounted transformer sub-station.

0 Answers  

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