Abstract: The invention relates to a system and a method for transmitting telegrams. The system has at least one first communication means provided for sending telegrams and at least one second communication means provided for receiving telegrams, with a telegram having a check value that can be determined from a useful data component of the telegram, with the first communication means having a first telegram counter provided for assigning a count value to a telegram in accordance with a send sequence. To improve error detection during the transmission of telegrams it is proposed that the count value for determining the check value be a constituent of the useful data component is, that information signaling a change in the count value be a constituent of the useful data component when the telegram is transmitted, that the second communication means have a second telegram counter, and that means be provided for synchronizing the first and second telegram counter.

Abstract: An electronic circuit having an input, an output with an input filter for delaying a change of an input signal and a control component for supplying an output signal and evaluating the input signal. The delay is a time constant. An industrial automation system is provide with the electronic circuit and a fail-safe component connected to an input and an output of the circuit. To increase the probability of detecting errors in the electronic circuit, the control component is provided for supplying a test signal for output through the output, for making a first evaluation of the input signal to be provided immediately after the output of a test signal and for making a second evaluation of the input signal after expiry of a time after output of the test signal which at least corresponds to the time constant. A method for testing an electronic circuit is also provided.

Abstract: An electronic circuit having an input, an output with an input filter for delaying a change of an input signal and a control component for supplying an output signal and evaluating the input signal. The delay is a time constant. An industrial automation system is provide with the electronic circuit and a fail-safe component connected to an input and an output of the circuit. To increase the probability of detecting errors in the electronic circuit, the control component is provided for supplying a test signal for output through the output, for making a first evaluation of the input signal to be provided immediately after the output of a test signal and for making a second evaluation of the input signal after expiry of a time after output of the test signal which at least corresponds to the time constant. A method for testing an electronic circuit is also provided.

Abstract: The invention relates to a system and a method for transmitting telegrams. The system has at least one first communication means provided for sending telegrams and at least one second communication means provided for receiving telegrams, with a telegram having a check value that can be determined from a useful data component of the telegram, with the first communication means having a first telegram counter provided for assigning a count value to a telegram in accordance with a send sequence. To improve error detection during the transmission of telegrams it is proposed that the count value for determining the check value be a constituent of the useful data component is, that information signaling a change in the count value be a constituent of the useful data component when the telegram is transmitted, that the second communication means have a second telegram counter, and that means be provided for synchronizing the first and second telegram counter.