SAFETY CIRCUIT ASSEMBLY FOR SWITCHING A HAZARDOUS SYSTEM ON OR OFF IN A FAILSAFE MANNER

摘要

A safety circuit assembly for switching on or switching off a hazardous system in a failsafe manner has an evaluating device which is designed to produce a redundant switching signal. The evaluating device is connected to a signaling device via a first and a second line forming a pair of lines. The signaling device has an actuator which can be switched between a defined first state and at least one further state. The evaluating device produces a first defined pulse signal and transmits the first defined pulse signal to the signaling device using the pair of lines in a first direction. The signaling device produces a second defined pulse signal, which is a predefined replica of the first pulse signal, and transmits the second defined pulse signal to the evaluating device using the same pair of lines when the actuator is in the defined first state.