A system includes a monitoring module configured to: receive a first indication related to a three-phase input of a three-phase AC electrical asset; receive a second indication related to a three-phase output of the three-phase AC electrical asset; determine performance metrics for the three-phase AC electrical asset based on the first indication and the second indication; determine error metrics by comparing each determined performance metrics to a pre-determined estimated performance metric; compare each of the error metrics to one of a plurality of pre-determined thresholds, the thresholds being determined when the three-phase AC electrical asset is in a healthy condition; and determine whether a developing fault condition exists in the three-phase AC electrical asset based on the comparison.