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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 ASi Master, an ASi power supply, the yellow ASi cable, and the ASi slaves. Using piercing technology, sensors and actuators are connected directly to the ASi cable. The unshielded two-conductor cable carries both power and communication, including safety signals. As a result, AS-Interface eliminates cumbersome parallel wiring. The ASi Master controls the data communication on the network. As a Gateway it creates the connection between the ASi network and the controller (e.g. PLC). The upper-level fieldbus treats it like a fieldbus slave. Integrating an ASi 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 ASi 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