Interpretation of rating of the primary voltage of a real transformer
The kVA rating is a measurement of power for the transformer (volts x amps) without taking the phase angle into consideration. 

The 2300/230 signifies the transformer ratio (primary/secondary). A 2300V (rms) input should give a 230V (rms) output.

Assuming the transformer is 100% efficient then the volt*amp products of the primary or secondary should be the same. However, in the real world, the secondary power (out) will be less than the primary (in). So taking the worst case senario then use the primary product (2300 * I(in)) = 15 000 giving a max input current of 6.52 amps.