Electric motor drive for using an AC electric motor or a DC electric motor, which electric motor drive comprises - safety switches determined by the safety of the electric motor drive, - a controlled mechanical brake, as well as a power supply circuit of the brake control, - a power converter, which power converter comprises a network rectifier and a power rectifier of the motor, which power rectifier of the motor is at least partly implemented with controlled semiconductor switches (9, 10) arranged into a bridge, - which power converter comprises an intermediate circuit (11,12) between the network rectifier and the power rectifier of the motor, - and which electric motor drive comprises a switch arrangement, which switch arrangement comprises normally-open switches (13, 14) in the intermediate circuit of the power converter, of which the first switch is connected in series to the positive intermediate circuit busbar between the output of the network rectifier and the input of the power rectifier of the motor, and the second switch is connected in series to the negative intermediate circuit busbar between the output of the network rectifier and the input of the power rectifier of the motor characterized in that the power rectifier of the motor comprises: - a quick-stop switch, and - an amplifier circuit connected to the control pole of the controlled semiconductor switch, the electricity supply of which is arranged to occur via the aforementioned quick-stop switch, and in that the semiconductor switch (9, 10) is fitted to switch into a conductive state when the amplifier circuit is in a controlled active state, and in that the amplifier circuit supplied via the aforementioned quick-stop switch is fitted alternatively either in connection with the controlled semiconductor switches connected to the positive intermediate circuit busbar, in connection with the controlled semiconductor switches connected to the negative intermediate circuit busbar or in connection with the controlled semiconductor switches connected to both the positive and the negative intermediate circuit busbar (9, 10). - safety switches determined by the safety of the electric motor drive, - a controlled mechanical brake, as well as a power supply circuit of the brake control, - a power converter, which power converter comprises a network rectifier and a power rectifier of the motor, which power rectifier of the motor is at least partly implemented with controlled semiconductor switches (9, 10) arranged into a bridge, - which power converter comprises an intermediate circuit (11,12) between the network rectifier and the power rectifier of the motor, - and which electric motor drive comprises a switch arrangement, which switch arrangement comprises normally-open switches (13, 14) in the intermediate circuit of the power converter, of which the first switch is connected in series to the positive intermediate circuit busbar between the output of the network rectifier and the input of the power rectifier of the motor, and the second switch is connected in series to the negative intermediate circuit busbar between the output of the network rectifier and the input of the power rectifier of the motor - a quick-stop switch, and - an amplifier circuit connected to the control pole of the controlled semiconductor switch, the electricity supply of which is arranged to occur via the aforementioned quick-stop switch,