Answer / k.prakashchandra

LAVT is abbreviation for lightning arrester and voltage
transformer (PT)which can be used for measurement ,synch and
protection.

Answer / sudarshan

excitation transformer is alternate to pmg in case of generator excitation,its rating is same as excitation required by generator.
in case of failure of pmg generator main main exciter can be excited through excitation transformer.

excitation trans----.
......main exciter.....rotor
pmg----------- .

We use ungrounded DC system (220V/110V) for control and protection system in substations etc. Suppose we have long 2 core DC cables running from our DCDB in control room to the load (length of around 2 to 3 km). Do we need to protect these long DC cables from earth leakages or not? If yes how?

5 Answers   Siemens,

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what is the use of sdf?

0 Answers   Areva, SWAN,

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How is the AVR working?

1 Answers  

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What is Scott connection? In which device it is used?

4 Answers  

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in our 6.6kv motor feeder[it is having two sources from Bus A&B] earth fault relay is acting, we checked CBCT connection and cable meggerd values found very good still earth fault acting during first two are three start after that it will hold. please clarify what was the reason. if same motor is starting from other Bus-A it will start.

1 Answers   Gasal, Voltech,

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i have 3, 75hp motors and 10, 15 hp motors....and to run this motors continously with a generator how much rating(kva) of generator will suiteble....?

2 Answers  

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what is function and advantage of double delta winding in induction generator?

1 Answers  

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what is the main parts of transformer? how it is functioning? pls giv the ans briefly.

0 Answers  

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what is the significance of tan delta testing?explain the theory?

7 Answers  

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when we have to use UPF wattmeter and LPF wattmeter? what is the difference between UPF and LPF wattmeter in terms of construction?

4 Answers  

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what is thermal setting and magnetical setting?

1 Answers  

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What is meant by reactance voltage?

0 Answers  

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