Why no-load primary current is very small
as compared to full load current in transformer (as 1% of
full load current?

Answers were Sorted based on User's Feedback



Why no-load primary current is very small as compared to full load current in transformer (as 1% of..

Answer / jonathan r. lambert

Normally, when power is applied to a transformer the
resulting primary current will be the vector sum of the
primary impedance and the reflected (turns ratio squared)
secondary impedance. However, since the secondary impedance
is infinite at no-load the reflected secondary impedance
will not influence the primary current and the primary
current will be the result of only the primary circuit
impedance. This no-load primary current is referred to as
the primary magnetization current and represents the
current used to excite the transformer's magnetic field
that links the primary and secondary windings - typically
1% to 5% of the full rated load current. Applying a load to
the transformer secondary will result in a primary current
with two components, the reflected secondary current and
the primary magnetization current.

Is This Answer Correct ?    34 Yes 11 No

Why no-load primary current is very small as compared to full load current in transformer (as 1% of..

Answer / gunasekaran

no load current is used only for energising the core so it
is 1-2% of full load current

Is This Answer Correct ?    11 Yes 1 No

Why no-load primary current is very small as compared to full load current in transformer (as 1% of..

Answer / san

no load current is only d 3-5%of full load current.if
alternating current is applid to d primary then no load
current wl flow through only primary circuit since
secondary is open circuitd.whn load is connected to the
secondary then current wl flow through the secondary
aswell..thats y we cn conclude that no load is smaller than
full load currents..

Is This Answer Correct ?    10 Yes 5 No

Why no-load primary current is very small as compared to full load current in transformer (as 1% of..

Answer / masoom raza

when secondary is open circuit the current in primary
is low i.e only magnetizing is present to create flux
in core.but when load is connected in secondary side it
produces its own ampere turn N2I2 which reduces the flux
in core . in order to maintain the flux constant, primary current increases to balance N2I2 i.e
N1I1=N2I2(neglecting magnetizing current)
therefore primary current increases when load
is connected.

Is This Answer Correct ?    3 Yes 3 No

Why no-load primary current is very small as compared to full load current in transformer (as 1% of..

Answer / azam

No load pr-current of a transformer is only 1-3% of FL
current because when supply applied 2 t/f it produce
alternating flux which induces emfs in primary & sec wdgs
with in the fraction of second. where as in the case of motor
starting current drawn by it is very high due 2 no presence
of back emf

Is This Answer Correct ?    3 Yes 6 No

Post New Answer

More Electrical Engineering Interview Questions

If a manufacturer decribes a power supply transformer as providing a secondary voltage of 24 volts when connected to a 240 volts supply, do you think they are refering to the full load or no load secondary voltage?

3 Answers  


Why power factor is arising in electrical circuit, is it possible to eliminate from the circuit, why

2 Answers  


why we are having many type of vector group in the transformer ,what is the use of it?

2 Answers  


the distance from my office to d.g is aprox 400mtrs and voltage drops ibn my office near about 40 volt what should i do p[ls suggest.

4 Answers  


why the earth terminal in three pin top is longer than rest of the two terminal and of bigger size?

6 Answers   BARC, MAHINDRA,






what is the role of transistor in Circuit?

0 Answers  


If R and Y terminals are short circuited,then power will cut. we all know that power cannot be stored.what will happen to already generated power at power station?

3 Answers  


What will happen to magnitude of voltage of other two phases if one phasw will touch the ground?

3 Answers   Construction, NPCIL,


Why single core cable required bonding at double end.

1 Answers  


How earth resistance reduses by pouring water coal and salt?

4 Answers  


what is the speed of a turbine in an hydroelectric power station and how many poles does it have...?

1 Answers  


what is main difference between live tank and dead tank current transformer?

2 Answers   Atul,


Categories
  • Civil Engineering Interview Questions Civil Engineering (5085)
  • Mechanical Engineering Interview Questions Mechanical Engineering (4451)
  • Electrical Engineering Interview Questions Electrical Engineering (16632)
  • Electronics Communications Interview Questions Electronics Communications (3918)
  • Chemical Engineering Interview Questions Chemical Engineering (1095)
  • Aeronautical Engineering Interview Questions Aeronautical Engineering (239)
  • Bio Engineering Interview Questions Bio Engineering (96)
  • Metallurgy Interview Questions Metallurgy (361)
  • Industrial Engineering Interview Questions Industrial Engineering (259)
  • Instrumentation Interview Questions Instrumentation (3014)
  • Automobile Engineering Interview Questions Automobile Engineering (332)
  • Mechatronics Engineering Interview Questions Mechatronics Engineering (97)
  • Marine Engineering Interview Questions Marine Engineering (124)
  • Power Plant Engineering Interview Questions Power Plant Engineering (172)
  • Textile Engineering Interview Questions Textile Engineering (575)
  • Production Engineering Interview Questions Production Engineering (25)
  • Satellite Systems Engineering Interview Questions Satellite Systems Engineering (106)
  • Engineering AllOther Interview Questions Engineering AllOther (1379)