Why do we give DC excitation to AC Synchronous motor??

9 Answers   Lance, MBM, Polycab,

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can we transmit power with out cable if it is possible how it is possible.

2 Answers  

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I am getting above 60 V as open delta voltage against single phase unit ICT at tertiary delta formed and ICT getting trippped on NDR. ICT tested and found in order. PTs provided on tertiary are tested and in order. what may be the reason?

0 Answers  

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generator means

1 Answers  

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how does an encoder work???

0 Answers  

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in a induction motor if we put capacitor across it will the power factor of the motor will improve? if yes how

6 Answers   Reliance,

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what is reactive power?

8 Answers  

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WHAT IS THE DIFFERENCE BETWEEN UNDERVOLTAGE COIL, CLOSING COIL AND SHUNT TRIP COIL OF AN ACB?

2 Answers   Alstom,

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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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how to increase or decrease speed in DC shunt motor by DC convertor

0 Answers  

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any calculation method for decide cable size for current?

1 Answers  

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(1)Electrical power is generated in KV, power consunmed is in MW and the transformers used are in KVA. How is KVA converted to MW as power being consumed by the consumers? (2)What is vector group of a transformer?

1 Answers  

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