Abstract: Method for controlling the use of a data-processing workstation (1) by password, comprising storage of the password within the workstation and, at each initialization of this latter, acquisition of a password proposition followed by a comparison of this proposition with the stored password. The password is stored in a controlled-erasure permanent memory unit. In order to release the workstation (1) in the event of loss of the password, provision is made for generation (D1) of a set (36) of data associated with the blocked workstation, communication (D2) of part of these data by the user to an authorized service (S), supply (D3) in return by this service of coded release data (43), acquisition (D4) of these latter by the user on the workstation, thereby resulting, in the event of compliance, in erasure of the initial password and in release of the workstation. Application in an industrial environment to control of the use of offline or network workstations.

Abstract: An input card (7) is put in communication with apparatuses (16) the operation of which is to be monitored in order to initiate certain operations. A terminal-box (13) is interposed between the card (7), which possesses detector circuits (17), and the members (16).The two ends of each circuit (17) are associated with a respective inner terminal (12) of the terminal-box (13), and the two ends of each member (16) are associated with a respective outer terminal (14) of the terminal-box (13). Shunts (19,21) mounted in the terminal-box and connected to supply terminals (14a,14b) put one of the ends of each circuit (17) or member (16) at a common potential. The other terminal of each member (16) is connected to the other terminal of a circuit (17) by means of a connection (18).The invention is used to avoid the need for auxiliary terminal-boxes and cards with a common potential point.

Abstract: An input card (7) is put in communication with apparatuses (16) the operation of which is to be monitored in order to initiate certain operations. A terminal-box (13) is interposed between the card (7), which possesses detector circuits (17), and the members (16).The two ends of each circuit (17) are associated with a respective inner terminal (12) of the terminal-box (13), and the two ends of each member (16) are associated with a respective outer terminal (14) of the terminal-box (13). Shunts (19,21) mounted in the terminal-box and connected to supply terminals (14a,14b) put one of the ends of each circuit (17) or member (16) at a common potential. The other terminal of each member (16) is connected to the other terminal of a circuit (17) by means of a connection (18).The invention is used to avoid the need for auxiliary terminal-boxes and cards with a common potential point.