Abstract: A safety device for an elevator includes a cabin, a counterweight, a cabin drive motor with a rotor, and at least one power-failure electromechanical brake. The safety device has a control device arranged to receive at least one information allowing emergency power to be applied to the brake in order to release the rotor, and allow the cabin blocked between two floors to move under the effect of unbalance between the weight of the cabin and the weight of the counterweight; to receive information enabling the speed of the cabin to be known; and to manage power supplied to the brake in such a manner as to enable the cabin to move to an evacuation floor while preventing the speed of the cabin from exceeding a predefined limit. The information that enables the speed of the cabin to be known is provided by at least one electrical magnitude from the motor.