Answer / lalith udawela

machine consumption power(haspre defined power factor,but
it may be too varry a few) is rating with kW, As well as
machine generate power is rating with kVA.

Answer / shyamal

Load of the Generator is not defined, so it have different
power factor of different loads therefore its rating in
kva, but in motor is an inductive load so its rating in kw

Answer / hafsal

the generator working is depending up on the current and
voltage given as input hence it is mentioned as KVA rating.
and also the motor is driven as the power input is given so
that it is rated as KW

Answer / md.azhar equbal

The main reason is that we can't measure the transformer power factor so that's why it's rating is in KVA and motor is in KW.

Answer / zahid iqubal

for generater and transformer first we do not know the
types of load it may be resistive, capacitive or inductive.
thats why for rating we consider no load condition. in no
load condition core losses and copper loss will be there.
as we know that core loss depends upon voltage and copper
loss depends upon current and in no load condition there
nothing types of losses which depends upon power facter.
there fore both are rated in product of voltage and current
not in KW. but moter is not subjected to resistive,
capacitive or inductive load it have fixed power factor
which is decided when it is desining

Answer / ankit bhandari

In order to understand this clearly you first have to know
what is POWER FACTOR.??
P.F= active power/(active power + reactive power)..reactive
power is that power which is applied to the motor's rotor to
create more magnetic flux so that greater amount of torque
developes on the rotor for better speed.that reactive power
depends upon the
a)Air gap.
b)No.of windings.
i.e,if there is less airgap less reactive power will be
required and if there is more air gap large reactive power
is required. this is why motors have there different power
factor.so due to this rective power pf is taken into account
in case of motors.which means P=VI x Power factor.(KW)
WHILE, if we talk about generators we are applying
mechanical energy to the rotor means there is no rective
power is required.means only active power is being developed
so there is no power factor.which means P=VI(KVA)
I HOPE YOU UNDERSTAND...

Answer / lakshmikantha reddy

Generator can deliver electrical energy ,so it doesn't
depends on power factor whether it is resistive/reactive.so
it is also rated in KVA.

Transformer transfers the voltage level , so it doesn't
depend on connected load and power factor whether it is
resistive/reactive.so it is also rated in KVA.

Motor can deliver only mechanical load and depend on
connected load is Reactive/resistive. so it is rated in KW.
An copper losses will be more in motor if the load
increases so theat load current increases and phase angle
between voltage and current will increse(PF decreases)

KW = VISin(Phi)

Answer / ramesh

Generator is producer of Voltage and Current, we can
connect load as such draining full load current or half
load, even noload,but voltage remain moreover same.So it
willl rated in terms of product of V*I, secondly it gives a
electrical output for any Load(may Capacitor,Inductor &
resistor),so it is consider as Procuct of Voltage & Current
excluding powerfactor.
Whereas motor is machines coverts electrical Energy to
Mechanical energy, so it is rated in KW.

Answer / zulfiquar ali wani

Generator rating is in KVA because the power of the load is not known, and the motor rating is in KW because motor has its own fixed Power factor

Therefore genrator capacity shown in KVA (
Without PF ) and motor Capacity shows in Kw ( with power
factor )

Answer / peter

All the answers are good...

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