2. If 8.35%Z means the percentage impedance of 132/11kV transformer self,will like to reconfirm the percentage impedance that is supplied from power company?

2 Answers  

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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  

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how to do 'pole drop test' on AC generator?

1 Answers  

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WAT IS MEANT BY COLD AND HOT START OF A MOTOR?? HOW DOES IT AFFECT A MOTOR'S PERFORMANCE??

4 Answers  

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is there interlocking between duty and standby chilled water pumps?

1 Answers  

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why transformer are rated in KVA not in watt?

7 Answers   DMRC, L&T, TCS,

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what is the roll of power factor in induction motor.

3 Answers   Hindalco,

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what is the principle of operation of tungstun bulb ??

2 Answers   IOCL,

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WE HAVE A LOAD OF 55KW MOTOR ITS VOLTS 380 3PH AND ITS TAKING 100AMPS (ITS FULL LOAD IS 105AMPS)AND ITS CABLE IS 4CX50SQMM ,NOW ITS GETTING ABNORMAL HEATUP IN CABLE,PLZ TELL WHY ITS HEAT-UP?(CABLE LENGTH IS 15 METERS ONLY)

10 Answers  

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how much current capacity 250 amp. mccb please tell me about whats are the reasons to trip 2 or 3 times in a night. and what are the steps to short out this problem

1 Answers   Havells,

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How much current does a motor take in no load condition?

6 Answers  

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what's the exact magnitude of current, flows through Neutral?

0 Answers  

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