if 20 hp motor starts directly stars and contenious run . what will be the effect.

11 Answers   HP, Ohsung Electronics,

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Auto transformer starter gives the same effect as star/delta strater if its turn ratio = A 0.5 B 0.67 C o.66 D 0.577

1 Answers  

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Which oil is used in Transformer?

6 Answers  

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what is the purpose of reactor in electrical substations ?

2 Answers  

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why do we need transformers?

12 Answers  

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If the line voltage is reduced to 75% of its rated value then by what percentage current will reduce ?? 75% 25% 50% no change and why ?

0 Answers  

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Can any body describe me why a soft starter is used for 6.6kv induction motor instead of VFD ?

1 Answers   Cairn,

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One of our gas turbine generator unit "1st stage rotor ground fault" alarm was occured several times. we tried to measure some voltage vulue ground fault protection relay (UNS3020a made by ABB and we measured the value of: Ground: 0.9VDC 5V: 5.8VDC 24V: 23VDC u+: 300 – 350mVAC Rf1: 17.5mVAC Rf2: 17.6mVAC The unit still running and the alarm was reset. As of 6pm yesterday and unitl now no alarm happened again. I our protection relay was defective?

1 Answers  

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Can I use 1 phase power supply to run 3 phase motor? If yes, how?

6 Answers  

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what is V=4.44FBN, THIS 4.44 ONLY U GOT the voltage in term sof 11, 22 etc this 4.44 u will get from form factor which has a value of 1.11

1 Answers  

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Why induction motor can not be operated at synchronous speed?? what would happen if it is operated at synchronous speed??

5 Answers  

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What is mean by nominal voltage,Explain?.How much nominal voltage?.

1 Answers  

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