Answer / rajesh

blowers for blowing cooled air inside train
fan for exhaust hot air
compressor ( dc /induction motor ) for cooling liquid
refrigerant to gas phase

pump for assisting flow if exhaust is above toilet at roof
ckt breaker , switch panel for control
temperature , pressure sensor
lead acid battery in case of express train
etc

An 11kv system consisting of an underground cable to a sub station about 300 meters away was shut down for about 10 hrs. On energising, it tripped off on earth fault about 10---20 mins later 6 times but since than it is not tripping.its already 3 weeks now. The SPAJ was found to be fine. what could be the cause.No test had been done to determine the cause of the trippings till now because of demand.

2 Answers  

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when giving a supply to wounded coil it will get magnetised, but the same is not if it is not wounded on a core..and it is getiing short....why.......

3 Answers  

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arrange to send solved question and answer its easy to study and understand the thing, because of Exam is to be conducted shortly

1 Answers  

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power factor is max for which welding a.arc b.resistance c.gas

2 Answers   Bhel, HCL,

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What is core CT & it's function?

0 Answers  

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raleigh method

0 Answers  

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How to put breaker in service / test position.

1 Answers   KSEB, L&T, Siemens,

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is it possible to step down voltage of single phase from a three phase sysem? explain

2 Answers  

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what is the use of vcb & isolator in substation?

4 Answers  

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what are fluorescent lamps (fluorescent fixtures) & what are incandescen lamps (incandescents fixtures) ? differences between these two ?

1 Answers  

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What is meaning of DRU in gen.of AVR.

2 Answers  

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I decided to provide a 11KV / 440V Xformer in my Substaion. What are the protection required for that?

5 Answers  

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