Answer Posted / ramamoorthy

VFD : VFD serves two purpose(smooth starting and speed
control):
a. Smooth starting by gradually increasing the source
power to rated output (by maintaining V/F ratio).
By starting at zero frequency & zero voltage (thus
the starting current also) and gradually increasing
the same to rated value.
b. Controls speed not only during starting but also at
rated voltage.

Soft starter serves only one purpose (Smooth
starting):

a. Smooth starting by gradually increasing the source
power only by increasing the voltage from zero
to full voltage and not varying the frequency like
autotransformer.
b. Cannot control speed at any point of time.

hi, could someone help me to find a control design for syncronising panel .

1685

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impliment (AB)`+C to transistor representation

1820

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I am interested to know what does 15 KVA DG set actually means? If I dont know the DG rating, is it possible to identify KW by simply knowing the diesel consumption?

2148

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what is plunger and what's the use of it in motor alignment?

2633

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what is electrical machines

3648

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why you don not show protection and type of isolation in key single line diagram?

1958

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Can anyone explain me about the RLC based Impulse high voltage generator and how to and operation of Series resonant High voltage reactor...?

1916

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In the formula : Knee point voltage = Burden X alf / class, Please inform what is alf? regards Shashidhar M.R.

4205

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how are reversing the direction of rotation of dc motor

1754

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How to decide CT & PT ratings for a given transmission line carrying some rated voltage?

2318

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what is negative and zero impedance in 3 phase induction motor ??

2149

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EXPLIAN THE IMPORTANCE OF POLY PHASE CIRCUIT.

2153

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Why the cores of large transformers build up of circular cross section?

2279

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plz tell me,ht and lt panel terminals in substations explain beiefly

2913

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What do you mean by transformation ratio of instrument transformer?

1087

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