What is the difference between PT and normal transformer?

What is the difference between PT and normal transformer?  
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1 Answer

Answer :

Burden of PT is less and burden of normal transformer is high.  
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Related questions

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Last Answer : The burden value in Potential Transformer (PT) should be high to achieve low errors in PT: 

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Description : What are the checks on CT & PT?

Last Answer : a) Polarity checks b) Insulation checks c) Ratio checks d) Knee point voltage (only for PS class CT)- magnetising characteristic test. 

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Description : What is the purpose of CT & PT?

Last Answer : For transformation of current, voltage to a lower level for the purpose of Measurement, Protection and Control. 

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Last Answer : Mho relays will mal-operate if PT voltage is lost to the relay, so tripping blocked by sensing PT fuse failure. 

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Last Answer : 24 kV, 3.15 Amps.  

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Draw a neat sketch and explain the use of CT and PT for measurement of power in a single-phase circuit?

Description : Draw a neat sketch and explain the use of CT and PT for measurement of power in a single-phase circuit?

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Description : To achieve low PT error, the burden value should be ____________. (A) low (B) high (C) medium (D) none of the above

Last Answer : Ans: A In a Potential transformer, burden should be in permissible range to maintain errorless measurement.

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Description : The boundary of the protective zone is determined by the (A) Location of CT (B) sensitivity of relay used (C) Location of PT (D) None of these

Last Answer : Ans: B The boundary of the protective zone is determined by the sensitivity of relay used. If the relay is more sensitive, the protective zone will be increased.

An open coil in a transformer will be indicated by which of the listed conditions? A. 'zero' resistance accompanied by high inductance B. no resistance accompanied by stray inductance C. infinite resistance in addition to no inductance D. infinite resistance in addition to normal inductance

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