Hi. Why does one conduct an open-circuit and a short-circuit test on a transformer to determine its equivalent circuit parameters? I've read that a) the open-circuit test determines the parallel parameters - the R and X equating to the core loss, and b) the short-circuit test determines the series parameters - the R and X equating to the winding loss and leakage flux. I've done this experiment in the lab, and have all the relevant raw data. I'm just looking for some understanding in why certain parameters can be ignored in the open-circuit case and must be considered in the shoty-circuit case, and vice versa. Cheers.