Answer / ruddho

Percentage differential protection and high speed high set
overcurrent relay are used for 5MVA and above power
transformer.
Reference book:Switchgear protection and power system.

Answer / velu5185

1.EARTH FAULT
2.OVER CURRENT
3.OIL TEMPERATURE
4.WINDING TEMPERATURE

How to calculate the NGR value for a 2.7MVA Transfomer, 11KV system where the fault current has to be limited to 50A?

1 Answers   Sterling Wilson,

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What is In (current rating) shown on the MCCB? Is this full load which can withstand by the circuit breaker

4 Answers  

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how can decide the current rating of oltc

0 Answers  

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what are lightning masts?what is their purpose???

1 Answers   Mecon,

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1.why are not using acb 33kv ht side? is there any problem 2.what is difference between acb,vcb,sf6 breackers? 3.what is the function of invertor and convertor in ups?

0 Answers   L&T,

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Pls tell me what is the exact current conducting capacity of copper and aluminium cables?how much capacity of cables need to 90kw induction motor&how?

1 Answers  

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how do u calculate CT rating for 10 mva transformer

2 Answers   Enercon,

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Basic motor transformer generator

0 Answers   eCentric Solutions,

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with help of neat sketch explain principle of TIG welding process

0 Answers  

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1. transformer design formula ? 2. how to calculate the primary turns and secondry turns ? 3. core types ? 4. how to find the primary current and secondry current ? 5. how to calculate the stacking factor ? 6. range of fulx density ?

2 Answers   Automation, Indian Railways, Mogora Cosmic,

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why can't we increase the voltage by increasing the field voltage in order to get higher voltage.so that we can eliminate step up transformer

4 Answers   Bhel,

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WHEN THESE TRANSFORMERS WINDINS CONFIGURATION ARE USED? SPECIALLY EXPLAIN REGARDING STEP UP AND STEP DOWN KEEPING IN MIND.AND REGARDING LOAD ALSO. a.star to delta b.delta to star c.delta to delta d.star to star ALSO EXPLAIN WHY V USE 415/415 TRANSFORMERS IN TUBEWELLS?

1 Answers   ABB,

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