Answer / gajanan

there are two losses occure in transformer viz. Cu loss and
iron loss.
Cu loss depends on current & iron loss depends
on voltage and not affected by power fector hence always
transformer ratting defined in KVA not in Kw.

Answer / prabahakaran

WE know the relation of power in three phase =
√3VIcosØ.hence we can say that the load is not constant it
very accordingly. So power factor is also get vary with
load it is hard to define the power of transformer so it is
rated in KVA.

Answer / gaurav bhardwaj

Rating is any device,s power capacity..so if u know how much useful power u can get then only it will be in kW..bcz power factor plays role in useful power then we can say that if a transformer has 20kva rating then it will deliver 20,kw at pf=1..Nd as we don't know the load which is to be supplied that's y rating in kva ,as kW=kva*pf

Answer / eng. d

I like the answer which is talking about the cu losses and
characterstic of the transformers.

let me drive the answer from differint angle.

let us assume that we told you that, the transformer is 20
MW, and now you want to connect motor of 15 MW to this
transformer, are you able to start this motor from this
transformer before the protection setting trip the circuit
breaker of the transformer?

I don't really know!! because I don't know how much
reactive power in this transformer, in other words, I don't
know how much losses in this transformer, then I can't do
prpoer analisys of the motor starting without knowing the
MVA rating.(which will include active and reactive power)

my advice, please try to do motor starting analysis on ETAP
or Matlap or any electrical softwaer and play with the
reactive power and see the differance and you will be clear
more ^_*
good luck

Answer / chinna

trf rating in KVA,current measures in amps&voltages
measures in volts.thats trf rating in kva.

What is Gnat,Ant,Rabbit &Dog overhead conductor? Please explain.

1 Answers  

function of soft starter .

2 Answers  

why to need a electrical earthing?

2 Answers  

Please explain how to do 'tan-delta test' on AC generator? and where i get clear and brief detail, give any web page address.

1 Answers  

How to increase the backup of three phase ups?

1 Answers  

why h parameter are called as hybrid parameter?

0 Answers  

Why we apply only reduced voltage to the alternator while conducting slip test ? also the current increases to a larger value with reduced voltage itself Why ?

1 Answers  

What is the use of 1:1 isolation t/f in any circuit...?

3 Answers  

wat is d first thing to be seen 2 lay a cable in a particular area??

1 Answers  

how can we find of cable capicity in amper?how much ampere withstand by 300sqmm cable?

1 Answers  

Three phase power is measured with two wattmeeter for balance three phase load.the reading of one wattmeter is zero.we can conclude that the power factor of balance load is?

1 Answers  

1. name the relay for protecting transformer 2. Current Transformer 3. potential Transformer

1 Answers