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The calculation of high voltage side of the transformer

Transformer capacity / 1.732 / HV side voltage equals HV side current
Low-voltage side of the current calculation
Transformer capacity / 1.732 / low side voltage equals low side current

For example, 1000KVA transformer high and low side of the current calculation:
High side current is 1000 / 1.732 / 10 = 57.736A
The low side current is 1000 / 1.732 / 0.4 = 1443.41A
Power calculation formula
Single-phase electric power calculation formula:
P = U phase × I × COSφ
Three-phase electric power calculation formula:
Knowing the total three-phase current, calculate its power consumption
P = 1.732 × U line × I × COSφ
(Cosφ power factor is generally between 0.7 ~ 0.85)
Such as: transformer capacity of 500KVA
The power factor is increased from 0.7 to 0.95 and the capacity needed to compensate for each kilowatt of power is 0.691 kilohertz, then: 500 × 0.691≈346 (kilo)

Motor actual power calculation
Motor power = 1.732 × rated voltage × actual current
Three-phase motor to single-phase motor capacitance formula
C = 1950 × I / U × COS
Where I is the three-phase motor Y connected to the current when the connection (nameplate marked), U is a single-phase 220V voltage, cosφ marked on the nameplate. The company is located in:

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