Answer Posted / aditya shirbavikar

Free wheeling diode (Fwd) is used in a d.c circuit, generally in a.c drives in which two stages are used to convert FFFV to VVVF. first rectification and then inversion. so, free wheeling diose is placed between rectifier bridge and invertor bridge so to prevent the reverse a.c pulses from blowing up the rectifier bridge circuit.

Is it possible to obtain 480v or 550v in single phase output by giving the input to 230v to a single phase torodial type transformer without using a stepup transformer?

1981

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while doing high voltage test on 11kv/433 distribution transformer why we only give 28 kv on hv side and 3kv on lv side for power transformers what is the value what factors it depends

2843

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What type of DC motor would you see for a lift?

1073

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1.how many types of relays? 2.difference between ATS& STS?

2144

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What are the advantages of using distance protection schemes as opposed to normal overcurrent/ earth fault protection on high voltage feeders.

3571

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anyone please send transformer parameter design formulas & details of tap changer ? plz i have interview this week its more helpful for me ?

1847

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When we connect the large capacitor bank in series ?

1075

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What is the difference between electronic regulator and ordinary electrical rheostat regulator for fans?

1091

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How can we calculate the KVA rating of a Distribution transformer from its core details?

2044

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PLEASE SEND THE PREVIOUS YEARS QUESTION PAPERS OF RRB JUNIOR ENGINEER-ELECTRICAL

1876

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why power not passes in plastic and rubber material

1953

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EXPLAIN THE WORKING OF SERIES REACTOR IN HT CAPACITOR BANKS (FOR VOLTAGES & CURRENTS)

8248

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please send me privious exam's queation papers of section engineer(electrical).

2047

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For high frequency application we use which transformer?

1909

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why zero sequence impedance measurement is not applicable for single phase GT

2182

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