Answer / rahul faye

A variable-frequency drive (VVVFD) is a system for controlling the rotational speed of an alternating current (AC) electric motor by controlling the frequency of the electrical power supplied to the motor. A variable frequency drive is a specific type of adjustable-speed drive. Variable-frequency drives are also known as adjustable-frequency drives (AFD), variable-speed drives (VSD), AC drives or inverter drives

Answer / saravananp

In Electrical:- VFD(Variable Frequency Drive). This is used to monitoring and controlling the speed of the driven based on the variation of frequency.

In Mechanical:- This is used to control the flow of air within the duct in terms of CFM(Cubic foot Metre).

which gas is filled in CFL

7 Answers   Lumax,

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how we control the magnitude of a generator output

2 Answers   EESINT,

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I'm generating a pulse of 3V with frequency 80Hz (12.5ms time period) and pulse duration 0.125ms and feeding it to a transformer since i want the pulse to get amplified around 60V. At the output amplification s happening but the pulse is changed to a spike, can you tell me what could be the reason? (an ordinary transformer 220V-12V stepdown transformer is reverse connected ie. now it is 12V-220V stepup and voltage amplification happens)

0 Answers  

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1)What will you do if main incomer VCB fail in your site ?

7 Answers   Honeywell,

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Can we use generator transformer as step down transformer? How?

3 Answers  

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What are the possible causes if load is not same on all the three phases

4 Answers  

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what is cathodic protection and why it use in industries?

0 Answers  

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Hi,Any one has idea regarding the KPTCL Recuirtments for AE'e & JE's for the year of 2009-10???Kindly help in regards..

2 Answers  

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Convert a star connected network into a delta connected network.

0 Answers   Syntel, Visa,

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What the formula for calculating no.of earthings & size of earth strip for 100mX90m shop.

0 Answers  

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Why mostly the HV side of transformer has Delta?

0 Answers  

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Is it possible to import & export power through the same power transformer? what will be the vector group normally for both different or same?

1 Answers  

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