What is the rated current of a 1250kva transformer? The rated current of the high voltage side of the 1250kva transformer is I=1250000/(10000*1.732)=72A, and the rated current of the bottom voltage side of the 1250kva transformer is I=1250000/(400*1.732)=1804A.

Calculation method of rated current of 1250kva transformer:

1250 refers to the transformer volume, all of which are apparent power, enterprise kVA. When calculating the current, use the formula to calculate: current = 1250/(1.732*U), and the measured value is the full current RMS. Short-circuit capacity means rated apparent power or apparent volume, the two are the same, but the names are different.

The primary side is 10kv, then the primary rated current S=root number 3*U*I,I=1250000/(10000*1.732)=72A

If the working voltage of the secondary side is 400V, then I=1250000/(400*1.732)=1804A The characteristics of the processing plant are different, and the power factor of the electricity consumption is also different.

For example, an ironmaking plant dominated by electric heating equipment has a high power factor; a production line dominated by motors has a low power factor.

Therefore, it should be estimated based on the rated current of the load, not the power factor.