How can i check a relay good or not?

2 Answers  

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what are d/f between cfl and pl lamps,

1 Answers  

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What are insulation classes? Tell examples of each of them.

1 Answers   IOCL,

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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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What is difference between MCB,MCCB,ELCB and RCCB? Brief description and why RCCB is costly?

3 Answers   JLL,

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In a 11000/440 V transformer, when any one phase of 11 KV supply fails (ie., single phasing), what happens to the secondary voltage and why?

3 Answers   Secure Meters, TCS, Torrent Power,

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give single line diagram of D.O.L and star -Delta starter ?

8 Answers   ABS, Al-Shuaah, Alkali Metals, Cabin Crew, Cognizant, CRI, Gwalior Distilleries, Hotels, Logicon Engineers, Max India, Nicomet, Radisson Blu, RK Company, Siemens, SLCM, Solar, Steel Strips Wheels, Sugar Factory, TATA, TCS,

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What is George phenomena to start the synchronus machine?

0 Answers  

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what is power factor ? why is it so important?

2 Answers   Telco,

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Hello seniors m an engineering student in 3rd yr..i want to know what are the software course in electrical field?i wanted to do certification course but i dont know much about the course?..Regards

0 Answers  

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What is the need of earthing transformer for delta side of a transformer. (Think of a line section between a star/delta transformer at a grid substation and delta/star transformer at a village. An earthing transformer is there at the delta side of the star/delta transformer at grid substation). As there are no ground reference there will not be fault current if a one phase is grounded. Further L-L phase will be sensed by the primary side of star/delta transformer as a L-G fault. So why an earthing transformer is required at delta side

0 Answers   CEB,

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Why don't connect earth wire to elcb?if earth fault occur,how will detect it

1 Answers   TATA, Tata Communications, Telecommunications,

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