Answer / ashli

in transformer core loss depends on voltage n cu loss
depends on current and power factor has no influence..
so we express in kva rating
in case of motor rotational loss, loss due to friction
windage loss etc are present. we cant express these losses
in kva

Answer / shanmugam

Basically, transformer losses always depending the rated
voltages & rated current. Because the core losses
calculated by open circuit method with full rated voltages
& the copper losses calculating by short circuit method
with full rated current.The losses of transformer is
depending the voltages(V) & current(A).Hence, we saying the
transformer capacity in KVA. The above not in motor

Answer / adnan kauchali

Simplest and Guaranteed answer is :
KW and KVA are Active power and apparent power resp.
where Active power(W) needs Power factor known
and apparent power is without power factor.
The Motor's power factor is known so it can be written in
Active Power rating

where in case of generator, there are several connected
loads having different power factor, so we can't calculate
the mean power factor of connected loads hence its rating is
without power factor ; that is VA (volts x amp)

Answer / tameshwar singh

I think that motor is designed for any defined power o/p &
its load Pf is also known for that power thus we can give
its rating in kW. But in case of Xmer & alternator the load
is not fixed & so as the load PF thus its rating is given
in KVA.

Answer / raja

the main difference between the kw and kva is the power
factor
kw= v*I*cos@
kva=v*I

Answer / dpk_1fj

Motor having a fixed output,we cannot increase,while
transfor depend on what type of load going to be connect on
that,that's why transformer rating alweys in kVA.

Answer / n.chandra shekar

transformer core lose find by using apply only rated voltage
and copper lossees find out by applying full load current,so
we obtaian exact performance in case motor added a
rotational losees so that it will measuredin kw.tranformer
measured in kva it is fixed .negligible p.f

Answer / sumajan

I think In transformer & in generator the PF will be vary
depending up on the load connected with it, in motor it is
a inductive load & we can guess its PF, Usually for
inductive load PF will be 0.8 lagging.

Answer / gunasekaran

motor output is mechanical so KW.
transformer is electrical output so KVA.

For what purpose an AVR in generator sensing generator output voltage?and how the sensing is done by AVR?

3 Answers  

respetsed sir, i have applied for section engg and juniour engg for both chennai and tiruvunabthapur boards for electrical deportments . can u suggest what books i have to follow and and also from which sections they r going ask (i mean weightage and what topics i have to cover) for both se and je for both chennai and tiruvunanthapur boards.......

1 Answers  

what is the eight bit unit?

0 Answers  

how to find 5 kilo meter long under ground 33 kv cable fault location if IR VALUE shows 0.05 M ohm @5000 volt.and cable fault locator shows some time fault distance 3 kilo meter ,3.7 kilo meter and some time 1 kilo meter? now how to find the fault location that where is leakage.

1 Answers   FGI, OPS,

On PVC conduit the class "A" "B" or "C" is marked what does it shows. Either its thickness or its composition?

2 Answers  

What is the difference between earth and neutral

4 Answers   ABB, Tamboli Engineers,

How much current will a 5 HP delta connected motor at no load will take?Is tat need a starter

2 Answers   GRB,

what is pilot wire protection? wer is it using?

1 Answers  

how to calculate the change over time for star delta starter for different KW motor?

0 Answers  

how can maintaince the acb contactor moveing and fixing kit

0 Answers   Gulf Cement,

Show formula which gives full load current 4.8 amps of a 3 HP motor and 27 amps of a 20 HP motor having 3 phase 460 volts, 0.8 Pf.

2 Answers  

what is the difference between relay, contactor

4 Answers   BRSS, Vishay Intertechnology,