A transformer draws inrush current that can exceed saturation current, affecting the magnetic property of the core. This happens if the transformer has no load with its secondary open. The magnitude of the inrush current depends on the instant on the AC wave at which the transformer is switched on. If that instant happens to be such that the AC voltage wave is going through its peak value, then there will be no inrush current drawn by the transformer. The magnitude of the current, in this case, will be at normal no load value.