Abstract: A device is adapted to be associated with a group of input or output channels, especially of a programmable automatic controller, to detect if the channels are subject to an open circuit and/or an overcurrent. To each channel are assigned two analog comparators connected to a processor logic circuit which connects one or the other comparator output to a control unit. Configurator logic activates or deactivates one or the other of the comparators and associated forcing devices and filters according to the operating mode selected.

Abstract: A device for controlling and protecting outputs against overcurrents, in particular for programmable automatic controllers, comprises for each output channel a protection circuit connected by a single terminal to a power switch and to its control circuit. In the protection circuit a comparator compares with a threshold a voltage imaging the current in the output channel and disabling means are connected to a circuit for forcing the comparator input voltage. A common terminal is therefore used to monitor and to disable the output channel.

Abstract: Output control circuit for a programmable logic controller, comprising a control unit (13) and a circuit (14) for controlling and checking output channels (11), including a deserializing section (16). The output circuit receives descending frames (T1) and ascending frames (T2) and, according to its configuration, it returns ascending frames (T3) to the control unit produced from frames (T1) and/or (T2).

Abstract: An input or input-output management circuit for a process control system such as a programmable automation is provided, including a serializing means with parallel inputs connected to input channels by filtering and threshold means, a series output of the serializing means being connected via a series connection equipped with an optocoupler and a filter to an input or input-output management unit.

Abstract: An input/output device monitors the transmission of information between a processor of a programmable controller and sensors and actuators of a process to be controlled. This device includes electronic circuits adapted for calculating the parities of the digital words which pass therethrough, these parities being compared with corresponding parities calculated by the processor which thereafter invalidates the words having two different parities.

Abstract: An input/output device is used for a programmable controller having on input/output cards a plurality of electronic channels forming the logic interfaces between the connection bus with the central unit and the sensors or the actuators connected to the controllers; this device further uses electronic circuits for monitoring the good transmission of input/output signals by the adaptation interfaces providing for the galvanic isolation of the bus with respect to the sensors and actuators of the controlled automatism.

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.