Answer / mahesh-lanco

The Main Functuion of the Insturments Transformers(Current
Transformer &VOLtage Transformers) is to Standartise the
secondary to less value. As the Relays and Circuit breakers
are designed at Very Low Values(DC).If the fault curent or
voltage is very high there is no meters manufactured for
the measurment of such high volatgaes/currents the
Secondaries of CT &PT are standartized to 5Amp and 100V
respectively

Answer / abhik raj

it is standard that CT sec should be 1 or 5 amp based on
partys demand.becz relay/meter are designed for the
same.otherwise it is difficult for both manufacturer/user.

why we dont store the ac power in battery?

1 Answers   TCS,

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I have a question, I visit 01 site and face a problem, there is 2.5 ton Air Con working, when air con compressor is running at that time rectifier voltages are increasing upto 290-295 v and rectifier is giving main high alarm (rectifier is APC single phase, before starting compressor rectifier voltages was 230v. when air con is going off rectifier voltages are decreasing smoothly at its actual voltages 230v. Load on Genset phases is this: Red-13.5 amp AC (Air Con load), Yellow-1.7 amp AC (BTS lights etc.) and Blew-4 amp AC (telecom system load), Genset phase to phase and neutral to phase voltages are also ok. These are 10 sites having same system and same rectifier APC brand at every site 02 genset are working but the problem is same at all these 10 sites. What will be the reason behind???

1 Answers  

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we touch other end of the tester supply, why do not get shock?

7 Answers   L&T,

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the site measured knee point voltage of protection class CTs should be greater than rated knee point voltage? what about meetering class CTs. Should it be below the rated knee point voltage?

0 Answers  

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what is the voltage regulation for unity and zero power factor?

0 Answers  

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What is P.F? Formula for calculating PF in HT side?

1 Answers  

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working principal of online ups

0 Answers   Delta Power Systems,

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Why 11KV PT Secondaries [(11000/1.732)/(110/1.732)/ (110 / 3)]are in star connection ? And why the same should not be in delta ?

1 Answers  

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In separetly excited m/c,we excite the field by a dc source,what not with ac source?

2 Answers  

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can we do the star delta connection of capacitor for 3- phase motor starter.

0 Answers  

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determine two methods to find loose connection in operational electrical system?

0 Answers  

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Size of the power cable like 1.5,2.5,4 sq.mm which area calculated from whick area or how specified the size?

1 Answers   MRF,

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