Question

100 kva transformer.how many kilowatt to be connected what is the formula

Answer 1

Transformer has three ratings, Voltage, current and kVA (apparent power). Generally it is adequate to specify voltage rating and either current or kVA rating, because,

kVA = Voltage * Current / 1000 for single phase

And

kVA = 1.731 * Voltage * Current / 1000 for three phase.

Maximum permissible value of load current corresponding to 11 kVA of apparent power is calculated below:

For single phase:

kVA = Voltage * Current / 1000
11 = Voltage * Current / 1000
11*1000/Voltage = Current
Current = 11000/Voltage.

For three phase:

kVA =1.73 * Voltage * Current / 1000
11 = 1.73 * Voltage * Current / 1000
11*1000/(1.73 * Voltage) = Current
Current = 6351/Voltage.