The addressable Input/Output Modules FI700/MM1IN1OUT and FI700/MM1IN1REL serve for the line-monitored connection of contact detectors to a loop and for the actuation of external devices via the loop with Labor Strauss protocol. In this way manifold devices such as manual call points, supervising contacts, fire doors, sirens or solenoid valves can be easily integrated into loop-based fire detection systems. The bi-directional communication on the loop allows for a fast actuation of the output and an accurate evaluation of the status of the module and the connected detector. An integrated dual-isolator disconnects the loop in case of a short circuit. In this way, the undisturbed communication with the loop elements outside the faulty loop section is ensured.