Answer / kashifhabib

Efficiency = (Output/Input)*100
&
Output (KW)= KVA * Power Factor
Input = Output + Iron losses + Copper losses
Iron losses are due to Primary voltage so remains constant
can be calculated by open circuit test
Copper losses are due to secondary current I*I*R
can be calculated by short circuit test
Exp: Full load copper losses 800 W
1/2 load copper losses will be 200 watts

Answer / vinod parasa

Efficiency = (Output/Input)*100
output=(x)(KVA * Power Factor)
input=(x)(KVA * Power Factor)+(X)^2 copperlosses+core losses

the volue of x depend on load
x=1 for full load
x=0.75 for (3/4)th load
x=0.5 for half load
x=0.25 for quarter load

copper losses are variable losses and iron losses are
constant losses.

at the time of full load copperlosses=iron losse
Full load copper losses 800 W
half load copper losses=(X)^2 copperlosses
x=0.5 for half load
=(0.5)^2 *400
=0.25*400
half load copper losses=200

Answer / n.makali

POWER Transformer is 55MVA, 27/11.5KV ,efficiency =99.49

Find the Losses of Transformer

Answer / s.ravi

Efficiency =
(Output/Output+Iron losses+Copper losses)*100
Iron losses = No load test,
Copper losses = Short circuit test
Regulation = (Impedance voltage/Rated input voltage)*100
Impedance voltage = Short circuit test(Voltage drop)

Answer / prof dr lehaz kakakhel

go for two tests
open and short circuits tests
From the open, u compute the core power loss and from the
short, u get copper losses. then the formula is
efficiency = output/ (output + the above two losses)
SIMPLE

Answer / ranag

repaired a 200 kva three phase distribution transformer his stander iron losses is 495 & copper losses is 3410 but the measured iron losses is 692 what formula is to know de-rated in kva ? pl answer with expal

how to improve power factor correction?

3 Answers  

How to connect frequency meter in metering circuit?(single phase and three phase frequency meter)phase to phase or phase to neutral

7 Answers   ABB,

what are pilot cells

0 Answers   KSEB,

If the Brush of DC motor is shifted by 90 deg, then what happens to voltage and torque? Both voltage and torque are zero. how to justify the answer?

0 Answers  

if the length, number of turns and area of coil are doubled then inductance of the coil becomes.?

1 Answers  

12.5 tons a/c is their how much kva generator can recommend to the customer.

0 Answers  

which bulb is greater iluminited, 60w and 100w are conected in series?

2 Answers  

what is neutral ground resistance relay? how it is helpful in protecting system?

5 Answers  

why fault current time duration is calculated for 1 minutes?

1 Answers   Rockfort Engineering,

How to calculate incoming cable size for 33KV, 1MVA transformer.

1 Answers   IAC,

What will happened if the neutral of the (star connected secondry) Xformer disconnected? (if its Above KVA rated one)

0 Answers   Equate,

High voltage test procedure of in swgr board. why should measure millivolt drop on testing time?

0 Answers   NTPC,