The invention relates to a motor lock, which can be used in particular in a fire protection door, comprising a bolt and an electric motor that can be coupled to the bolt. In the open position of the bolt, the bolt can be loaded into the closed position of the bolt by means of a preloaded spring unit. The motor can be coupled to the bolt by means of a coupling, which is held closed by means of an actuator so long as the actuator is supplied with current and is released by the actuator if the current supply drops out.