Answer / sunil ulange

ALL TRANSFORMERS RATING ARE IN KVA BECAUSE TRANSFORMER IS
INDEPENDENT OF POWER FACTOR AND TRANSFORMER WILL NOT ACT AS
A LOAD, IT ONLY TRANSFERS VOLTAGE FROM ONE LEVEL TO OTHER LEVEL.

KVA = KILO( VOLTS * AMPERES )

NORMALLY REACTORS RATINGS ARE IN KVAR

Answer / rajendra gadhe

Transformer reating is always in KVA because the losses of
T/F are depending upon voltage & current ,not on the phase
angle so that T/F rating is in KVA not in KVAR
( This topic u can study in the book Electical Enng Part 2
by B L Tereja.)

Answer / nag

TRANSFORMERS ARE RATINGS ARE IN KVA.WHY BECAUSE CORE LOSSES
DEPENDING ON VOLTAGE AND COPPER LOSSES ARE DEPENDED ON
CURRENT.SO,TRANSFORMER DEPENDING ON VOLTAGE AND
CURRENT .THATS WHY TRANSFORMER RATING IN KVA.
REACTIVE POWER IS RATING IN KVAR .

Answer / rijwan

someone has written that transformer losses depend on voltage as well as current that's why the rating is in KVA.
In case of motor also cu loss and iron loss depend on current and voltage respectively. Then the rating of motor why not in KVA ??
In case of x-mer we simply dont know the power factor as it operates at different power factor with time.
That's why the rating of x-mer is in KVA, not in KW.

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