Answer Posted / suresh kumar

There are many types of protection relays used in
transformers depend upon its construction, size, use etc.
They are
1. Buchholz relay for incipient faults like short ciruit,
winding temparature protection, oil temparature protection,
oil level protection, oil pressure protection, Pressure
relief valve (for oil filled transformers)
2. Differential protection
3. Thermal Protection
4. Earth fault protection
5. Over current protection
6. Over excitation protection(where OLTC is used) etc

What is mean by hot and cold loop testing? What is the difference between them?

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hi plz send me reliance placement papers..i.e electrical technical papers that have been asked in reliance test.

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Transmission voltage is kept 11KV,33KV,66KV,132KV,220KV due to form factor. What happen to 400KV and 765KV transmission voltage?

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Pl. brief about break-down maintenance of machine tool.

1798

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Please brief what is sinewave

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Can Anyone suggest the Standards (IEC or IS) for selecting copper current density?

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what is the difference between switchgear and circuit breakers and is there any difference between outdoor and indoor switchgear and circuit breakers , and how would you differentiate between switch yard and substation and grid station . thanks

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What do you mean by power transformer?

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How the setting of the vector surge relay shall be calculated when the relay is to be used for Grid islanding application?

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How do I calculate a WTI CT ofa 1250kVA 6600/400V transformer

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Explain how to determine capacitor tolerance codes?

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What happens if we give the supply to the rotor of induction motor and make its terminal shorted?

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what is JE exam?

2165

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how to find the multiplication factor for digital energy meter and analog energy meter

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what is meant by poly phase induction motor ? how its operating by single phase or three phase?

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