An apparatus for use in a power delivery system, the apparatus comprising: a DC circuit breaker having first and second terminals and configured to automatically switch from a closed state to an open state during an overcurrent condition; a disconnector switch in series with the DC circuit breaker, the disconnector switch having a first terminal for connecting to a first polarity terminal of a DC power supply, a second terminal for connecting to a second polarity terminal of the DC power supply and a common terminal connected to the first terminal of the DC circuit breaker, the disconnector switch having at least a first position in which the first terminal is connected to the common terminal and a second position in which the second terminal is connected to the common terminal; and an interlock mechanism coupled to the DC circuit breaker and the disconnector switch, the interlock mechanism configured to disable the DC circuit breaker from automatically switching from the closed state to the open state during the overcurrent condition when the disconnector switch is in the second position.

A switching device for an on-board electrical system of an electrically driven motor vehicle includes an electromechanical switch which is designed to connect and interrupt a supply line of the on-board electrical system. The electromechanical switch has: a stationary first switching contact, a movable second switching contact, and an actuation unit which has a mechanical force-transmitting element and a drive element. In order to switch from an open switching state to a closed switching state of the electromechanical switch, the drive element moves the transmitting element along a movement path, and the force-transmitting element moved along the movement path acts mechanically on the second switching contact and moves the second switching contact toward the first switching contact. In order to maintain the closed switching state of the electromechanical switch, the force-transmitting element applies, at the end of the movement path, a pressing force to the second switching contact for pressing against the first switching contact, without further driving by way of the drive element.

An apparatus for controlling current in a circuit may include a motor, a leadscrew coupled to the motor, and an actuator arm coupled to the leadscrew. The apparatus may include a common terminal, a normally open terminal, a normally closed terminal, and a contact arm configured to couple the common terminal to the normally closed terminal in a first position and to the normally open terminal in a second position. A spring can bias the contact arm toward the first position, and the motor can be configured to operate the leadscrew to move the actuator arm, and the actuator arm can be configured to move the contact arm from the first position to the second position.