Diifferential relay Stability testing for transformer

I need a help to find out whether the method adopted was right or it may have some effects on transformer.

We have 5 MVA 11/11 delta-star transformer with % impedance 12.6.

We want to test the stability of the differential relay ABB make RADHA.

We short circuited the transfomer secondary terminals in Breaker panel

first created zonal & then out of zone fault to test the relay stability.

We had give 440V 3Phase supply to primary while secondary was short circuited.

current observed to be 160Amps.

I want to know whether this test is okey or it may affect adversly on transformer performance due to the inrush current while short circuited mode.