Abstract

AS-Interface (AS-i) (actuator/sensor interface) was defined and developed by a consortium of 11 German and Swiss companies between 1990 and 1994. At this point in time, multiple different fieldbuses had already been developed, but none of them seemed to be suitable to connect simple sensors and actuators. Therefore, it was necessary to devise an entirely new type of a system with the primary goal to replace cable trunks and to minimize installation expenses. Thus, a system was designed based on a simple nonshielded two-conductor cable that was able to transfer data as well as 24 V power.