kVA Rating
The apparent power rating of a transformer in kilovolt-amperes, determining load-carrying capacity.
The kVA rating is the fundamental capacity of a transformer, representing maximum apparent power at rated voltage/frequency without exceeding temperature limits. Three-phase: kVA = V x I x sqrt(3)/1000.
Used instead of kW because thermal limits depend on total current regardless of power factor (1,000 kVA = 800 kW at 0.8 PF or 1,000 kW at unity PF).
Standard IEC ratings: 30, 50, 75, 100, 160, 200, 250, 315, 400, 500, 630, 800, 1000, 1250, 1600, 2000, 2500 kVA. Power transformers start at 5 MVA.
QDTB manufactures all standard ratings with custom options. Selection guide helps determine optimal kVA.
Related Products
Related Terms
Apparent Power (kVA)
The total power in an AC circuit combining real (active) and reactive power, measured in kilovolt-amperes (kVA).
Nameplate Rating
Manufacturer's certified specifications on the transformer nameplate defining all critical parameters.
Rated Capacity
The maximum continuous power output a transformer can deliver at specified conditions without exceeding temperature limits.
More Terms Starting with “K”
K-Factor
A transformer rating indicating ability to supply non-linear harmonic loads without exceeding temperature limits.
Knee Point Voltage
The voltage at which a current transformer core begins to saturate, critical for protection CT performance.
Kidney Loop Filtration
An online oil purification system continuously filtering transformer oil through a side-loop circuit to remove moisture and particles.
More in “Performance Parameters”
Core Loss
Power dissipated in the transformer magnetic core due to hysteresis and eddy currents, also called iron loss or no-load loss.
Copper Loss
Power lost as heat in transformer windings due to electrical resistance, proportional to the square of load current.
Efficiency Class (IE1-IE4)
International classification for transformer energy efficiency, IE1 (standard) to IE4 (premium) with progressively lower losses.
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