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Question
`what is the difference between KW and KVA?`
Question Submitted By :: Bharath
I also faced this Question!!     Rank Answer Posted By

Re: what is the difference between KW and KVA?
# 1
kw means that it is the power deliverd to the load. where
as the kva is the power can be meet the load demand. so
that kva is not with respect to load.

if we simply says kw=kva*power factor.

so that only alternators and transformers(giving supply,not
specified in kw.

 Is This Answer Correct ? 242 Yes 36 No
Navaneethan

Re: what is the difference between KW and KVA?
# 2
KW= Active power
KVA= Apparent power

 Is This Answer Correct ? 150 Yes 20 No
Imran

Re: what is the difference between KW and KVA?
# 3
kW is the unit of real power & kVA is the unit of Apparent
power.

Apparent Power= real power + reactive power

Looking at different electrical equipment you will notice
that the power ratings are either expressed in kVA
(kilo Volt Ampres) or sometimes in kW (kilo Watts). The
next question is what’s the difference? Both are
measurements of power however they are truly different.
To understand the differences consider how each are
derived. kW is called actual or real power, or simply
the amount of power that is available to do real work. kVA.
On the other hand kVA is known as “apparent”
power. This is because only a portion of the available kVA
may be available to do real work. The remainder
is simply excess current.
The difference between kVA and kW really depends on the
power factor (PF). When the voltage and
current are in phase with each other in an AC circuit, the
power factor is 1.0 or “unity”. The more the
voltage falls out of phase with the current the lower the
power factor becomes and the less “real power” or
kW the device uses; however it may still be using the same
amount of current as a device with a higher
power factor. Power factor will be "leading" or "lagging"
depending on which way the load shifts the
current’s phase with respect to the voltage’s phase.
Inductive loads cause current to lag behind voltage,

kVA = Volts x A
kW= Volts x Amps x Power Factor or [kVA x Power Factor]

The next question is why express the kVA value of a device
and what use is
kVA if only part of it can do work? The reason kVA is used
as a rating is
because the rating of an electrical device is dependent on
the amount of
current they can sustain. A kW rating does not indicate how
much current
a device can carry (as the power factor may not be known)
where kVA
does indicate the maximum current at a specific voltage
level.

 Is This Answer Correct ? 124 Yes 13 No
Raghav

Re: what is the difference between KW and KVA?
# 4
The power consumed by the resistive element of the circuit
with Impedance is termed as Active Power
P= V*I*p.f.
P=I*Z*I*(R/Z)
P=square(I)*R in Wattd
The power consumed by the Impedance of the circuit is
called as Active Power
S=V*I
S=I*Z*I
S=square(I)* Z expressed in VA

 Is This Answer Correct ? 8 Yes 31 No
Shyam Majgaonkar

Re: what is the difference between KW and KVA?
# 5
kw is a real(Active) power that depends on the load that we use.
KVA is a apparent power which is the maximum power that can
be produced by source.

KVA = voltage x current

KW= voltage x current x power factor

Apparent Power(KVA)= real power(KW) + reactive power(KVAr)

 Is This Answer Correct ? 62 Yes 15 No
Azarudeen

Re: what is the difference between KW and KVA?
# 6
KW means machanical power(mechanical load) o/p of the system
but KVA means electrical power output(electrical load)

 Is This Answer Correct ? 15 Yes 70 No
Maharajan

Re: what is the difference between KW and KVA?
# 7
in the ideal conditions the power of the load is equal to
its KVA , but practically a phase difference will happen
between the volt and the current and it will lead to reduce
the KVA to the KW , the ratio between the KW power (Actual
power ) & the KVA (Appearent power) is the power factor .
In my opinion we can say the KVA is the theoritical value
of the power , and it can be equal to the Kw if no phase
difference happened.

 Is This Answer Correct ? 28 Yes 8 No
Ammar

Re: what is the difference between KW and KVA?
# 8
kw IS THE POWER DRAWN BY A LOAD LIKE ELECTRIC
MOTOR,HEATER,FAN ETC,

WHEREAS kva IS THE POWER WHICH WE CAN GET FROM A POWER
CONVERTOR SOURCE LIKE INVERTER,UPS,DG ETC.
ALSO kw=kva*POWERFACTOR(VIcos&#511;)

 Is This Answer Correct ? 9 Yes 29 No
Rajinder Kumar

Re: what is the difference between KW and KVA?
# 9
kw IS THE POWER DRAWN BY A LOAD LIKE ELECTRIC
MOTOR,HEATER,FAN ETC,

WHEREAS kva IS THE POWER WHICH WE CAN GET FROM A POWER
CONVERTOR SOURCE LIKE INVERTER,UPS,DG ETC.
ALSO kw=kva*POWERFACTOR(VIcos&#511;)

in the ideal conditions the power of the load is equal to
its KVA , but practically a phase difference will happen
between the volt and the current and it will lead to reduce
the KVA to the KW , the ratio between the KW power (Actual
power ) & the KVA (Appearent power) is the power factor .
In my opinion we can say the KVA is the theoritical value
of the power , and it can be equal to the Kw if no phase
difference happened.

KW means machanical power(mechanical load) o/p of the system
but KVA means electrical power output(electrical load)

kw is a real(Active) power that depends on the load that we
use.
KVA is a apparent power which is the maximum power that can
be produced by source.

KVA = voltage x current

KW= voltage x current x power factor

Apparent Power(KVA)= real power(KW) + reactive power(KVAr

The power consumed by the resistive element of the circuit
with Impedance is termed as Active Power
P= V*I*p.f.
P=I*Z*I*(R/Z)
P=square(I)*R in Wattd
The power consumed by the Impedance of the circuit is
called as Active Power
S=V*I
S=I*Z*I
S=square(I)* Z expressed in VA

kW is the unit of real power & kVA is the unit of Apparent
power.

Apparent Power= real power + reactive power

Looking at different electrical equipment you will notice
that the power ratings are either expressed in kVA
(kilo Volt Ampres) or sometimes in kW (kilo Watts). The
next question is what’s the difference? Both are
measurements of power however they are truly different.
To understand the differences consider how each are
derived. kW is called actual or real power, or simply
the amount of power that is available to do real work. kVA.
On the other hand kVA is known as “apparent”
power. This is because only a portion of the available kVA
may be available to do real work. The remainder
is simply excess current.
The difference between kVA and kW really depends on the
power factor (PF). When the voltage and
current are in phase with each other in an AC circuit, the
power factor is 1.0 or “unity”. The more the
voltage falls out of phase with the current the lower the
power factor becomes and the less “real power” or
kW the device uses; however it may still be using the same
amount of current as a device with a higher
power factor. Power factor will be "leading" or "lagging"
depending on which way the load shifts the
current’s phase with respect to the voltage’s phase.
Inductive loads cause current to lag behind voltage,

kVA = Volts x A
kW= Volts x Amps x Power Factor or [kVA x Power Factor]

The next question is why express the kVA value of a device
and what use is
kVA if only part of it can do work? The reason kVA is used
as a rating is
because the rating of an electrical device is dependent on
the amount of
current they can sustain. A kW rating does not indicate how
much current
a device can carry (as the power factor may not be known)
where kVA
does indicate the maximum current at a specific voltage
level.

 Is This Answer Correct ? 9 Yes 15 No
Bhushan

Re: what is the difference between KW and KVA?
# 10
In the ideal conditions the power of the load is equal to
its KVA , but practically a phase difference will happen
between the volt and the current and it will lead to reduce
the KVA to the KW , the ratio between the KW power (Actual
power ) & the KVA (Appearent power) is the power factor .
In my opinion we can say the KVA is the theoritical value
of the power , and it can be equal to the Kw if no phase
difference happened.

The simple way is kw=kva*power factor.

 Is This Answer Correct ? 18 Yes 6 No
Kirankumar