Why a transformer is rated in kVA and not in kW??

Answers were Sorted based on User's Feedback



Why a transformer is rated in kVA and not in kW??..

Answer / md. samiul islam

In Transformer, there are two types of losses, One is copper
loss (Cu Loss) which depends on current and other is iron
loss which depends on the voltage. Hence total transformer
loss depends upon the Volt-Ampere (VA, so it is independent
of load power factor. This is why a transformer is rated in
KVA instead of KW.

Is This Answer Correct ?    22 Yes 2 No

Why a transformer is rated in kVA and not in kW??..

Answer / naresh kumar

In t/f there are two losse ,first loss is Cupper loos and
second is iron loss,which get current & Voltage
respectively.There is no any power factor that why we
measure the t/f in VA not in watt.So transformer is rated
in KVA not in KW.

Is This Answer Correct ?    18 Yes 5 No

Why a transformer is rated in kVA and not in kW??..

Answer / ashok bhatnagar

The current drawn by a transformer depends on the load
connected in the secondary. If the load cneected is a
resistive load the majority of current drawn is in pahse
with the supply voltage and transformer operates at near
unity power factor. In this case transformer supplies kw
nearly equal to its kva input. However if a inductive load
like motor is connected it draws lagging current and
operates at lower power factor. In this case trasformer
supplies lower kw as compared the kva drawn. Thus
powerfactor of a trasnformer depends on type of load
connected and hence it can not have defined kw rating. That
is why transformers are rated in KVA and not KW

Is This Answer Correct ?    10 Yes 1 No

Why a transformer is rated in kVA and not in kW??..

Answer / r sanjay

Tranformer windings are insulated copper wires and are
designed to carry a particular amount of current(depending
on the size/diameter/cross-sectional area of the
wire).Beyond this current the windings will get damaged due
to overheat. The current that flows through these windings
is dependent on the load connected to the secondary of the
transformer. Both active and reactive portions of the
current contribute to the current flowing through the
transformer windings. Thus the total current is the
limiting factor. Moreover, the insulation of the
transformer windings determine the max voltage that it can
support. Thus, the voltage and the current determine the
capacity of the transformer. this product in KVA defines
the transformer capacity. KWatts is the active power and is
lower than the KVA by a factor called pf(power factor).
Where Watts = Volts X Amperes X pf.

Is This Answer Correct ?    2 Yes 0 No

Why a transformer is rated in kVA and not in kW??..

Answer / karna

In Transformer Copper losses in current, Iron losses in
voltage , the total losses depends upon VA not in KW. And
there is no Phase angle between voltage and current. That's
Why we are Transformer rating in KVA( Killo Volt Amp)

Is This Answer Correct ?    0 Yes 0 No

Why a transformer is rated in kVA and not in kW??..

Answer / gurunadharao

Transformer design is independent of powrfactor, what about the distribution load is..thats y we are used capacitor bank in Lt load

Is This Answer Correct ?    0 Yes 0 No

Why a transformer is rated in kVA and not in kW??..

Answer / guest

P=VI
V=VOLTAGE v
I=CURRENT A
POWER IS THE PRODUCT OF VOLTAGE AND CURRENT

Is This Answer Correct ?    1 Yes 2 No

Why a transformer is rated in kVA and not in kW??..

Answer / guest

becouse t/f is a machine that transform the voltage. that
is not a power cosumable device. and we did not know how
types load to connect to the t/f means
resistive ,capicitive or inductive type so we have not
value of power factor.

Is This Answer Correct ?    0 Yes 3 No

Why a transformer is rated in kVA and not in kW??..

Answer / bhigesh

its problem of pf variation

Is This Answer Correct ?    3 Yes 11 No

Post New Answer

More Electrical Engineering Interview Questions

What is HT? And specify the range of voltage?

5 Answers   HSL,


Difference between divercity and power factor

1 Answers  


what is the formulae for selcting capacitor bank to increas pf

3 Answers  


List the power rating of any 5 important electrical appliances used in houses.

0 Answers  


what is destructive and non-destructive testing of welding

0 Answers  






what is booster? and how it is connected in a circuit?

0 Answers   APTransco,


Among the following Which is vector quantity? a. Flux b. permitivity c. flux density d. magnetic intensity

2 Answers  


how to find the voltage drop

1 Answers   Sharjah Electricity and Water Authority SEWA,


what is the difference between OSR and BUCHHOLZ relay of transformer?

1 Answers   Bhushan Power Steel,


How the neutral earthing is connected in DG alternator

6 Answers  


Why should not we run the IM in low voltage, if runs means what will happen?(for example instead of 400V we give 250V supply)

2 Answers  


formula for incomer breaker size calculation of powerfactor correction unit

3 Answers  


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)