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Question
`what is the function of commutator in dc motor?`
Question Submitted By :: Electrical-Engineering
I also faced this Question!!     Answer Posted By

# 1
in dc motor commutator converted DC to AC

in DC genator its function is AC to DC that's way we called
as commutator is a mechanical rectifier

 Is This Answer Correct ? 307 Yes 141 No
Zakeer

# 2
first of all ,it is dc motor not a generator.
We are already giving it a dc current ,so normally there
should not have been any need of commutator'
but as the armature is rotating, with every half
rotation ,the direction of rotation is reversed.
so it should be rotating in anti_clock wise direction for
half cycle and in clock_wise direction for next half cycle.
to cater this ,the direction of current should be reversed
after every half cycle.
that's why a commutator is used to change the direction of
current to cater the problem of torque

 Is This Answer Correct ? 101 Yes 12 No

# 3
in d.c motor commutator serves in produsing unidirectional
torque

 Is This Answer Correct ? 117 Yes 57 No
Murali

# 4
The DC Generator generate the AC supply only in Armature
not DC Supply.But we want Dc source , so want one converter
thats why we use commutator.In shortly we can say its
converts AC source to DC source.

 Is This Answer Correct ? 168 Yes 123 No
A.balakrishnan

# 5
A commutator serves two purpose in DC Machines-the first
one is to convert alternating quantities into direct
quantities and vice-versa and second is to keep the rotor
or armature MMF stationary in space.

 Is This Answer Correct ? 16 Yes 5 No
Rahul Thakur

# 6
first of all ,it is dc motor not a generator.
We are already giving it a dc current ,so normally there
should not have been any need of commutator'
but as the armature is rotating, with every half
rotation ,the direction of rotation is reversed.
so it should be rotating in anti_clock wise direction for
half cycle and in clock_wise direction for next half cycle.
to cater this ,the direction of current should be reversed
after every half cycle.
so, commutator is a converting d.c to a.c
because we are giving a pulse of every half cycle.that
called a function of commutator in dc motor

 Is This Answer Correct ? 10 Yes 0 No
Raju Kanjariya

# 7
Dear all please note commutator is not a converter, all are
telling dc ot ac, we already giving dc supply to motor
through motor terminals at A1 & A2 (ie.+ & -) it is
transformed to rotor winding or bars through Brush and
commutator.

DC supply - Motor TB A1&A2 - Carbon Brush - Commutator -
Rotor winding or copper bars

 Is This Answer Correct ? 46 Yes 41 No
Prabakaran

# 8
hey there,, i am in year 12 in one of the school In
Brisbane,, i guess i this is what i learn t at school..in
Physics Class.

A split rind commutator is a special switch assembly on the
rotating coil shaft that allows the direction of the current
through the coil to be reversed every 180 degrees .

Seema singh

 Is This Answer Correct ? 13 Yes 9 No
Seema

# 9
commutator function in the dc motor is to convert dc
quantity into ac, so it produces regular torque.
& in case of generator it converts ac quantity into dc.
THE FUNCTION OF COMMUTATOR IN DC MOTOR IS TO REVERSE THE
DIRECTION OF CURRENT.

thank you.

 Is This Answer Correct ? 5 Yes 1 No
Dharmesh

# 10
first of all before going to discuss about the function of
commutator in dc motor we need to know about the parts of
the machine.from the construction point of view dc motor is
same as that of dc generator but the operation is
different.it is a dc machine which can be operated as motor
by providing electrical energy or as a generator by
providing mechanical energy and excitation.we can call the
dc motor as doubly excited dc machine why because we are
providing excitation not only to the field but also to the
armature.But between the armature and the brushes we have a
mediator i.e commutator.if the commutator is stationary dc
is directly applied to the armature because of no induced
emf in the armature winding called beck e.m.f heavy current
will flow cause damage to the armature.if we made to run
the armature by providing low voltage to the armature the
armature will rotate .when the armature rotates the
commutator which is connected to the armature also
rotates,the commutator converts dc into ac to the
armature.so ac applied to the armature and the back emf
will be developed which regualtes the flow of currents
through the armature.this back emf will depends upon the
speed of the armature simply to say that the function of
commutatorin dc motor is to convert dc to ac

 Is This Answer Correct ? 2 Yes 1 No
B.anil Kumar

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