A method for configuring a failsafe module, which is connected to a field bus coupler of an industrial automation system via a sub-bus in order to transmit security-related data of the module via a field bus, utilizes a number of steps, The type of security protocol that is compatible with the field bus is determined via the field bus coupler, and configuration instructions are transmitted to at least one failsafe module via the field bus coupler in order to enable the module to use the determined type of security protocol. Furthermore, a field bus coupler or a system comprising a field bus coupler and at least one failsafe module is designed to implement the method.
