Answer / vasu

VFD are used to make the motor to run in desired speed. By
variying the input supply frequency we can vary the speed of
the motor. some other types are VVFD - Variable voltage and
frequency drive, Vector drive.

Answer / rawjaw

We know a relation speed
say,N=120f/p,speed directly
proportional to freq.In some
applications large motors
used to drive a heavy load,we
start such motors from 0 rpm
& provides initial torque(say
160%) in order to achieve
energy efficient.ok..

Answer / hitesh kareliya

VFD Means Variable Frequency Drive,So that means we
controll the Pump's RPM via VFD in desired frequency.

Answer / amit shetkar

see firstly vfd is basically used mainly for 2 purpose i.e to
protect electrical motors & for speed control.
& now about that star delta arrangement it used before motor
in that star connection is used to give smooth start to motor
& when motor achieve it's speed so to maintain that speed
delta connection is used

Answer / vinay singh

When the elements are connected in neither series nor parallel
to reduce network star delta arrangement is used.

Why would an Engineer consider combining FEEDBACK and FEEDFORWARD control in some applications?

4 Answers   Jindal,

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ON RADAR INTERFACE LEVEL TRANSMITTER IF DI-ELECRIC IS WRONG WITH CONTINIUS PROCESS THAN HOW CAN INDENTIFY OR HOW CAN I PUT NEW DI-ELECTRIC VALUE?(ROSEMOUNT-TDR-3300-COXIAL PROBE TYPE)

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what is pressure control

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1 Answers  

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What is a flow meter?

2 Answers  

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How to Calibrate Vortex Flow transmitter in field

0 Answers  

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An electronic p controller has an input range of 1-5v, and output range of 4-20mA, while testing a step change of 0.4 was applied at the input , the PB setting was 50% ,what should be the change in the output ?

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what is Dry Leg calibration and where is it used

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Sir , i have completed my M.Sc In Instrumentation and presently working in Maintenance department 3 yrs Exp , is there is any possible for work in offshore ..

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Close loop and open loop diagram for instrumentation

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please send the sample qustion paper for iocl written test ..

0 Answers   IOCL,

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