for selection of transformer we will considering 5 to 6
times of starting current of higher rating motor connected
to secondary side. according to process wise we will start
the motors gradually suppose if we will start 15 to 20
motors at a time wat will happen?



for selection of transformer we will considering 5 to 6 times of starting current of higher rating..

Answer / wareagle

If you start all of the motors at the same time then you
will have the sum of the lock rotor amps time the number of
motors occurring at the same time. You may trip the primary
transformer breaker.

Is This Answer Correct ?    4 Yes 0 No

Post New Answer

More Electrical Engineering Interview Questions

what is the difference between surge arrestor and surge supressor

1 Answers  


why did youi choose this career?

0 Answers   KTB, ONGC,


what are the applications of PLC?

0 Answers  


why electron flow is opposite to current flow?

3 Answers  


What is DPR relay, And what for??

2 Answers   Engro,






What is the technical reason for adopting color coding of three phase system as RYB.

11 Answers   ABB, ERDA,


how to calc. current for 5MVAR,50hz,33kv

1 Answers  


why in power staions distriution r like 11kv,33kv,66kv in india?

4 Answers  


why generation voltages are 6.6kv or 11kv and why not some one give that stander that generation voltages are 5kv or 12kv?

1 Answers   AES,


What do you mean by ACB and VCB?

3 Answers   L&T,


On load tap changer (OLTC) explode? Transformer Vector group: Ynd11 Rated Power: 353MVA Rated Current: 693A Voltage:294/20KV OLTC Type: T III Y1000 110/c 12193w Max Operation Current: 295A Step Voltage: 550V Arrangement in Tx windings: Y Connection Problem: Damage of Unit 1 Generator Transformer On Load Tap Changer (OLTC) Description of Incident: 9.00 a.m. :- Generator No Load test on excitation system started 10.30 a.m :- Carried out AVR change over test 11.30 a.m :- Preparation for Generator Manual Synchronizing test 12.00 a.m :- Manual Synshronizing test started. Observed incoming generator voltage higher than running voltage. CECR operator operated Generator Transformer OLTC to bring down the incoming generator voltage 12.03 a.m :-Generator Transformer abnormal alarm operated at Gen.Control Desk (CECR) CECR operater at Generator transformer bay informed that the transformer oil splashed out from OLTC. CECR operater informed that he heard explosion inside OLTC. Observed Oil level & Oil Flow alaram operated at Tranformer local annunciator. 12.05 am :- CECR operator 'Open Gen Field Breaker” 12.10 a.m. :- Elec1 team inspected the OLTC and found the OLTC rupture disk was broken and oil spilled at OLTC area. - Elec1 found the OLTC top cover bulging. Do anyone know why and possibility cause happen in this OLTC.

9 Answers  


Why in celling fan stator are rotatig while rotor are steday

6 Answers  


Categories
  • Civil Engineering Interview Questions Civil Engineering (5085)
  • Mechanical Engineering Interview Questions Mechanical Engineering (4451)
  • Electrical Engineering Interview Questions Electrical Engineering (16632)
  • Electronics Communications Interview Questions Electronics Communications (3918)
  • Chemical Engineering Interview Questions Chemical Engineering (1095)
  • Aeronautical Engineering Interview Questions Aeronautical Engineering (239)
  • Bio Engineering Interview Questions Bio Engineering (96)
  • Metallurgy Interview Questions Metallurgy (361)
  • Industrial Engineering Interview Questions Industrial Engineering (259)
  • Instrumentation Interview Questions Instrumentation (3014)
  • Automobile Engineering Interview Questions Automobile Engineering (332)
  • Mechatronics Engineering Interview Questions Mechatronics Engineering (97)
  • Marine Engineering Interview Questions Marine Engineering (124)
  • Power Plant Engineering Interview Questions Power Plant Engineering (172)
  • Textile Engineering Interview Questions Textile Engineering (575)
  • Production Engineering Interview Questions Production Engineering (25)
  • Satellite Systems Engineering Interview Questions Satellite Systems Engineering (106)
  • Engineering AllOther Interview Questions Engineering AllOther (1379)