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AS-Interface (short for Actuator/Sensor Interface) is an internationally recognized standard for field bus communication. With over 32 million nodes installed world-wide, it is heavily used at the sensor/actuator level of automation systems.

AS-Interface Installation

This simple wiring system consists of four components: the AS-i Master, an AS-i power supply, the yellow AS-i cable, and the AS-i slaves. Using piercing technology, sensors and actuators are connected directly to the AS-i cable. The unshielded two-conductor cable carries both power and communication, including safety signals. As a result, AS-Interface eliminates cumbersome parallel wiring. The AS-i Master controls the data communication on the network. As a Gateway it creates the connection between the AS-i network and the controller (e.g. PLC). The upper-level fieldbus treats it like a fieldbus slave. Integrating an AS-i network into an existing fieldbus or Ethernet system is no more complicated than adding any other I/O module.

Digital Modules with two times two flat cable connections (Click to enlarge)

Benefits of AS-Interface

  • Ease of use: The system can be operated and maintained with negligible training effort or specialized service personnel
  • Free topology: AS-Interface allows cables to be routed according to the mechanical structure of the system (line, start, tree or ring structure)
  • Fast, flexible installation and effortless expandability: New slaves can be added without error-prone and time-consuming cable assembly using piercing technology right on the AS-i cable
  • Effortless integration of new slaves due to standardized profiles
  • High availability and noise immunity
  • Great savings on planning, installation, expansion, and service time compared to parallel wiring systems
  • Certified products ensure manufacturer compatibility