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Question
What is the working principle of ceiling fan?
 Question Submitted By :: Electrical-Engineering
I also faced this Question!!     Answer Posted By  
 
Answer
# 1
The celing fan motor works on principle of single phase
induction motor using capacitor.
Working of capacitor start motor: The stator consists of
the main winding and a starting winding (auxiliary). The
starting winding is connected in parallel with the main
winding and is placed physically at right angles to it. A
90-degree electrical phase difference between the two
windings is obtained by connecting the auxiliary winding in
series with a capacitor and starting switch. When the motor
is first energized, the starting switch is closed. This
places the capacitor in series with the auxiliary winding.
The capacitor is of such value that the auxiliary circuit
is effectively a resistive-capacitive circuit (referred to
as capacitive reactance and expressed as XC). In this
circuit the current leads the line voltage by about 45
(because XC about equals R). The main winding has enough
resistance-inductance (referred to as inductive reactance
and expressed as XL) to cause the current to lag the line
voltage by about 45 (because XL about equals R). The
currents in each winding are therefore 90 out of phase -
so are the magnetic fields that are generated. The effect
is that the two windings act like a two-phase stator and
produce the rotating field required to start the motor.
When nearly full speed is obtained, a centrifugal device
(the starting switch) cuts out the starting winding. The
motor then runs as a plain single-phase induction motor.
Since the auxiliary winding is only a light winding, the
motor does not develop sufficient torque to start heavy
loads. Split-phase motors, therefore, come only in small
sizes.
 
Is This Answer Correct ?    211 Yes 25 No
Nilesh Vyas
 
Answer
# 2
See Gobindarout! we are not discussing here about
mechanical principles & air floating directions. The ques
related to how the ceiling fan working means what is the
electrical principle involved in that (working) while it
rotates, what is the reason to rotate?how it is starting &
whats the reason. think in that
manner............k
 
Is This Answer Correct ?    131 Yes 74 No
Ravi Teja.a
 
 
 
Answer
# 3
Ceiling fan is a Single phase Induction motor.Generally we use a capacitor start &Run AC Motor for ceiling Fans.
Motor principle: whenever current carrying conductor is placed in a magnetic field-it experiences force.
Stator: supplied by 1-phase voltage, current will produce in the stator winding-so magnetic field. But AC motor needs a rotating magnetic field in order turn the motor shaft (fan blades). This is done by applying voltage with different phases to different windings. In a single phase system (like at your house where you would use a ceiling fan) there is only one voltage phase. The capacitor is used to provide a phase shift (i.e. a time offset between currents) in the windings of the motor, making it appear that the motor is operating in a multiphase system.In Simple Terms, A single Phase is Split Into Two. There are also other methods to split Phase But using a capacitor is less expensive.
Now we have magnetic field.
We need current carrying conductor:
Because of Induction, voltage will develop in rotor as It is a closed circuit current will produce-so current carrying conductorp laced in magnetic field.
Rotor will rotate.
 
Is This Answer Correct ?    61 Yes 35 No
Eben George Babu
 
Answer
# 4
Ceiling fan is a Single phase Induction
motor. Generally we use a capacitor
start &Run AC Motor for ceiling Fans.
Motor principle: whenever current
carrying conductor is placed in a
magnetic field-it experiences force.
Stator: supplied by 1-phase voltage,
current will produce in the stator
winding-so magnetic field. But AC
motor needs a rotating magnetic
field in
order turn the motor shaft (fan
blades). This is done by applying
voltage with
different phases to different windings.
In a single phase system (like at your
house where you would use a ceiling
fan) there is only one voltage phase.
The capacitor is used to provide a
phase shift (i.e. a time offset between
currents)
in the windings of the motor, making
it
appear that the motor is operating in
a
multiphase system.In Simple Terms, A
single Phase is Split Into Two. There
are
also other methods to split Phase But
using a capacitor is less expensive.
Now we have magnetic field.
We need current carrying conductor:
Because of Induction, voltage will
develop in rotor as It is a closed
circuit
current will produce-so current
carrying conductor placed in
magnetic field.
Rotor will rotate.
 
Is This Answer Correct ?    26 Yes 5 No
Raghu
 
Answer
# 5
When fan rotates with the higer speed than air from top
side goes to the down side and the pressure of the top side
is negative pressure and pressuer bowards buttom side is
positive so, air moves from tp bottom
 
Is This Answer Correct ?    62 Yes 225 No
Gobindarouth
 

 
 
 
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