Answer / vinoth

In HT motors it will reduce the starting current up to 60 percent thats why we prefer star to delta conection..........but in LT motors we use Direct online starter/.......it doesnt reduce the starting current

Answer / madhu

The starting current for motors is 6 to 7 times full load current. So start-up power will be large if HT motors are delta connected. It may cause instability (voltage dip) in case small Power system. In starred HT motor starting current will be less compared to delta connected motor. So starting power is reduced. Starting torque will also be reduced. (It will not be a problem as motors are of high capacity.)

upto how many load can v connect to stabilizer which is used for tv

0 Answers   Sandvik,

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what is the use of buchzloys relay?

2 Answers  

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why different series of vfds (like allenbradley)are used in industry ?

0 Answers  

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differentiate PLC,DCS,SCADA?

1 Answers   SAS,

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10 hp motor ,7.5 kw ,960 rpm, full load current 15.5, delta connection so how much take current no load trial time. any formula please give..... second question :- what is different between brekar control wiring and motor starter control wiring

1 Answers   MSP,

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according to ohms law ,the voltage increases then current is what happened?

4 Answers   NTPC,

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In TNC switch, is there any 1NO+1NC block ? and if we move over closing position, is ther any affect on trip position or vice versa?

0 Answers  

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we can stepdown the voltage from 230/12v ,and we use the voltage for various electronics components why can't we step up the voltage from 12/230v if we can shall we use the voltage for domestic single phase supply

5 Answers   Areva,

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Sir we have 12.5 MVA(110/11KV) transformer (Y-Y) connected,which tripped showing earth fault,when we charged transformer it stood OK ,but on connecting 11 KV feeders it tripped showing earth fault.our service engineers found that the B phase and R phase phase connecting to neutral broken from HV OLTC(on load tap changer),and R phase and Neutral is ok.Dissolved gas analysis shows that accetline content is high,tan delta value is 12.My dout is it is an internal fault of transformer,why REF or diffrential relay is not acted?

1 Answers  

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how many test is necessary for 27mva transformer.

3 Answers   HEG,

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why compound generator is used in generating station?

2 Answers  

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how many types erthig

6 Answers  

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