Answer / sakthivel perambalur

merits : 1, constant speed
2, to improve the power factor

demerits: 1, high cast
2,special application only

Answer / manoj9550336681

Merits:
Constant Speed.
De-Merits:
Requires Extra DC Supply for excitation.

Answer / ckp

M.-Motor rotates dm-no noise

Answer / deeksha jain

merit:for power factor improvement ,as a
"synchronous capacitor"
demerit:not self starting

Answer / mahesh katakdhond

MERITS

1.Run in Synchronous speed.
2.If load changed then run either synchronous speed or zero speed(magnatic locking).

DEMERITS

1.Not self start.
2.High cost.

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

0 Answers  

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How to define Kirchhoff current law and voltage law along with simply examples.

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WORKING PRINCIPAL OF MCB

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1 Answers  

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what is tower earthing and what for it is required

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How can you test the vector group of power transformers?

2 Answers