A method to facilitate fault detection in the protected unit after connection to the at least a portion of the power system. A current is sensed in the protected unit during a plurality of different time periods. Compliance of at least one of the sensed currents with a respective first current criteria is determined based on a first current threshold value. On a condition that there is determined that at least one of the sensed currents comply with the respective first current criteria, a fault in the protected unit is detected.