what is the use of vcb & isolator in substation?

4 Answers  

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how to decide choke rating for drive?

0 Answers   Reliance,

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What is the requirement of sulphuric acid in electrical feild?

1 Answers  

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Relay setting for earth fault of reciprocating and centrifugal compressor motor feeder.Setting will be different or same?

1 Answers   Reliance,

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why transformer does not obey ohms low?

3 Answers   AITM,

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what is the function of a Master trip relay? why is it used ?

5 Answers   ABB, Nissi Engineering Solution,

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WHAT IS VFD,FUNCTION, PURPOSE,

2 Answers   RasGas,

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1. What is differential relay? How it operates? 2.How to calculate the Short Circuit Impedance in Transformer? 3.What is the alternate solution for testing of polarity by using polarity tester while its milli ammeter does not works? 4. While testing the 33KV Busbar by using Hipot kit, what should be the test voltage we have to apply? 5. What is the procedure/activities to be taken to inject the current more than 2000A by using 2000A Loading Transformer? 6. Explain how you can give the overload setting to any Motor Protection Relay for a HT motors with formula and example? 7. Why restricted earth fault protection is needed? Why can’t differential Protection is sufficient? 8. What should be the minimum and maximum ohmic value for earthing? 9. Why DC Currents are not used in transformer? 10. What is the Frequency while we step up the voltage from 220V to 11KV? Is it possible? Explain it?

0 Answers  

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what is the full form of KVAR

6 Answers  

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1 sq.mm alluminum cable hou much current caraing capacity

5 Answers  

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What is K-rated transformer? What is the use of it? What can be the size(pls provide calculation if possible) of K- factor transformer for 550kW,690V motor operating with drive (VFD)?

0 Answers  

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A 230V dc shunt wound motor has an armature resistance of 0,15Ω.When operating on no load at 650 rev/min the armature current is 6A . The motor takes a full load current of 85A. Calculate the full load speed if the field flux is (i) maintained constant (ii)reduced by 0,03

0 Answers  

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