Abstract: A method for determining a mean time to failure of an electrical device, and a method for adjusting a predetermined mean time to failure of an electrical power supply and for evaluating the adjusted mean time to failure. The method determines the mean time to failure by taking into account both operating conditions and operational load.

Abstract: A method for determining a mean time to failure of an electrical device, and a method for adjusting a predetermined mean time to failure of an electrical power supply and for evaluating the adjusted mean time to failure. The method determines the mean time to failure by taking into account both operating conditions and operational load.

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: 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: 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: The invention discloses a printed circuit card on which is welded at least an electronic component box as well as a thermal dissipator for dissipating the heat emitted by the component box. The component box and the thermal dissipator are respectively provided with clips and lugs which are engaged and welded in respective holes drilled in the card. A thermal drainage metallic area provided on a zone of the card located under the box forms a thermal adduction path between the box and the lugs of the thermal dissipator. This thermal drainage metallic area is further connected to a clip ensuring a privileged thermal drainage of the electronic component box.

Abstract: A DC power control circuit with status report and protection against overloads and short circuits is provided in which the output stage comprises at least one output amplifier whose input receives an external control logic signal and whose output is connected, through a current limiter, to the output of the circuit. The control circuit further comprises a voltage threshold detector which compares the residue voltage of the output stage with a threshold voltage corresponding to a maximum acceptable difference and which delivers a report signal representative of the sign of the difference between the residue voltage and the threshold voltage.