Switch-off device, high-voltage onboard electrical system, and motor vehicle

A switch-off device for a high-voltage onboard system of a motor vehicle, the switch-off device comprising:

• a current conductor for providing a load current path between components of the high-voltage onboard system,
• a pyrotechnically activatable separating unit for interrupting the load current path in an event of a fault, the pyrotechnically activatable separating unit having a separating element and a pyrotechnic element, wherein the pyrotechnic element is configured, in the event of the fault, to accelerate the separating element in a direction of the current conductor, and wherein the separating element is configured to separate the current conductor, for interruption of the load current path, and
• an arc quenching unit for quenching an arc which is generated upon interruption of the load current path, the arc quenching unit having a melting conductor which, under normal circumstances, is not incorporated in the load current path, and having a quenching device for quenching the melting conductor,
• wherein the separating element is configured, upon separation of the current conductor, to bend a current conductor piece for transfer of an arc generated on the melting conductor in a direction of the melting conductor, and thereby to incorporate the melting conductor in the load current path in the event of the fault which generates the arc, and
• wherein the bent current conductor piece and the melting conductor are arranged in an at least temporarily contact-free manner relative to each other during the transfer of the arc.