An example system includes a failure detection circuit. The failure detection circuit is to detect a failure of a first power source electrically coupled to a first load. The failure detection circuit is to output a first signal indicating the detection of the failure of the first power source. The system also includes a current regulating circuit. The current regulating circuit is electrically coupled to the failure detection circuit. The current regulating circuit is to electrically couple a second power source to the first load based on the first signal output by the failure detection circuit. The current regulating circuit is to restrict a first current from the second power source.