Answer / aruniscool

Can use 25 sq mm copper 3 core or
50 sq mm aluminium 3 core

ro plant grundfos bm30type pump.we start the pump using siemens 3rw 4423-1bc44, 30kw soft starter. bur its failier frequently. so we planed to change the dol starter. sp please tell me any budy its possible or not翿შ†

1 Answers  

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WHY NUTRAL GROUND SYSTEM USED IN 33KV SYSTEM

0 Answers   RasGas,

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To test Transformer we give HT side 440V to see wheather that it is producing 17.6V on LT to verify Voltage ratio is correct or not but when we give the 440V voltage to LT side then what will happen to HT voltage ?

3 Answers   Aditya Birla,

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Explain few advantages of electric traction system?

0 Answers  

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234 MVA Generator 3 phase Short circuit current Values required? Gen set Rating-234 MVA, Gen Voltage-18kv, PF;0.8, Xdv:23.5 %, Transformer Rating-18/380KV, 680MVA,Yndd1 two winding, Step up TR, ZT:35.50 %,X/R 4.33 Gen CB Position, CB open ,Disconnected open, Generator Running Voltage 18 Kv, Bi mistakes generator side earth switch Closed during that time short circuit current level in 3 Phase required, and how to test on site 234MVA Generator Short circuit current,

0 Answers   Jubail O&M,

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Why an ac systems are preferred over dc systems?

0 Answers  

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Main advantage of auto transformer over two windings transformer is that A it needs no cooling B it uses only one winding C core losses are reduced D it has simple construction

0 Answers  

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why voltage is low at reciving end in summer??

4 Answers   JSW,

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What are the transformer losses?

0 Answers  

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What is the difference between switch gear and control gear ?

2 Answers   QU,

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what should be 3phase motor capacity or rating to connect in star connection. what should be 3phase motor capacity or rating to connect in delta connection. what should be 3phase motor capacity or rating to connect in star delta connection

1 Answers  

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difference between servo motor and synchronous motor

0 Answers   Hitachi,

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