A circuit comprises a primary transistor connecting a primary voltage source to a load connector. A translator and a secondary transistor cause opening of the primary transistor when receiving an off command and cause closing of the primary transistor when receiving an on command. The secondary transistor is powered by a secondary voltage source. A microcontroller receives measurements of a load voltage at the load connector. The microcontroller detects a drop of the load voltage to determine a moment when the load becomes connected to the circuit while the off command is being issued. The microcontroller issues the on command in response to the determination. Successive brief on commands may be issued to initially control current build-up in the load. A system includes the microcontroller and a plurality of such circuits for powering plural loads.