The invention relates to a disconnecting device (1) for interrupting a direct current between a direct current source (2) and an electric apparatus (3), comprising a current-conducting mechanical switch (5), a power electronics unit (6) connected thereto, and an energy store (C9) which is charged by an arcing voltage generated on the switch (5) by an arc (LB) as the switch is being disconnected (5); a pulse generator (7) that is connected to the energy store (6) triggers at least one semiconductor switch (T1, T2) of the power electronics unit (6) in such a way that the power electronics unit (6) short-circuits the switch (5) and the arc (LB) is extinguished.