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.

how to design coil turns ?

1912

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Differentiate between low pass, high pass and band pass filter?

1006

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Please brief what is sinewave

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i have install 750 kva distribution transformer at my site and want to do neutral earthing. what calculations should i follow to determine earthing conductor material and size?

2002

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why we use four type of phase angle difference between pimary & secondry winding of a transformer & where we use them?

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where can the transformer having vector group Yny0 be used??

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PAC and simple Ac different

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How much load can take a 16 mm aluminum cable 3 phase

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What is a slack bus?

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2. A current i=(10+10 sin t)amperes is passed through MI type ammeter. its reading will be.........

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List the time domain specifications.

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how to fit 3 HP crompton gear motor with conveyor with the use of staring delta starter or ordinary starter?

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In electrical what is earth(ground)connection, wht is the importance of it, why it is recomended to maitain below 3VAC between Neutral and earthspecially in PLC used machines?

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Advantages/Disadvantages of earthing of neutral bus on MSB instead of separate neutral earthing for transformer/DG sets feeding to MSB

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