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).

Why use only DC supply to charge batteries why not AC Supply??

3 Answers   APC, Emerson,

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Is there any Institution (Not AMIE)for giving B-Tech/M-tech in Electrical engineering for those who r in service? Give the details please.

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WHAT ARE THE CHARACTERISTICS OF AN VOLTAG AMPLIFIER

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Hi, I've just got into my electrical engineering course and I need some help with a question of mine here. During a site visit, we were shown a main LT panel which has switchgears, ammeters and different kinds of relays and the distribution network from that panel. In the main LT panel I've noted down the current readings as Ir - 163A, Iy - 150A and Ib - 147A. The Line to Line voltage is 415 V at 50 Hz and Line to Neutral voltage is 230V at 50 Hz. From the above details, how would I calculate the kVA rating of transformer? The primary side voltage of the transformer is 11 kV and the secondary side voltage is 415V and the frequency is 50 Hz.

2 Answers  

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what is current

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in magnetic field we send current to generate flux,why not voltage?

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how to reduce earth to neutral voltage?

8 Answers   Field Gun Factory,

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17 Answers   Alstom, Call Centre, EDC, HCL, Procon Engineers,

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What are the condition for parallel operation of transformers?

2 Answers   Alfanar,

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What is transformation ratio what it describes?

0 Answers   Cushman Wakefield,

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what is photo voltic cell,& what are the materials associated with that?and any spcifications like volts/cm etc?

0 Answers  

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