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Automation Made Simple

AS-Interface is a globally standardized fieldbus system. Additional information on the benefits it provides, where it can be used and what you need to use it can be found here:

What is AS-Interface?

Data and power through a single cable
The abbreviation ASi stands for Actuator-Sensor Interface. This interface connects the modules in the lowest process level in automation systems with each other. The usual cable trees are replaced here by a single electrical cable – the ASi cable. This cable carries both data and power.

The four ASi components
Leading manufacturers around the world support this simple wiring system. It consists of four components: the master, the slaves , a power supply and the yellow ASi cable. Each slave has a unique address assigned to it which the master uses to exchange in- and output data. Insulation penetration technology means the modules can be quickly and easily attached or moved on the ASi cable.

Quickly identify and fix errors
Diagnostics units or masters with built-in diagnostic functions make troubleshooting easier. Failed slaves can be quickly identified, replaced and automatically re-addressed by the master.

An all-round good idea
In short: ASi is a system requiring little installation and maintenance effort, saving time and money. Additionally it is one of the simplest field busses, making its handling possible without specialized knowledge.

Simply a Powerful System

ASi allows you to freely choose your topology. For example

Safety – so problem-free
AS-Interface lets you even realize safety-relevant (EN ISO 13849) and noise-immune installations.

Installation – so simple
AS-Interface pioneered a clever installation technology with its unique flat cable. Simply insert cable, tighten down, and you're done.

Compatibility – so open
Operate with virtually any bus system: PROFIBUS, PROFINET, CC-Link, EtherNet/IP etc.

Costs – so low
AS-Interface drastically reduces wiring and installation cost and makes expansion or retrofitting very simple.

AS-Interface: Market and Facts

  • There are more than 37 million active ASi devices worldwide
  • 7 million of these are safety devices

  • Over 2.000 certified products
  • Safety relevant units with around 70% growth rate

Components of the ASi Network

AS-Interface Master

connects sensors and actuators through the ASi slaves to the higher-level controller.

AS-Interface Slave

reports to the master, has its own address and up to four in- or outputs.

The Cable

sends data and power over two conductors.

The Power Supply

supplies the ASi network with 30 volts.


Factory Automation

Vehicle Automation

Process Automation

The brewery, which recently opened in April 2019, was designed and built by the brewery experts GEA Process Engineering A/S. All the brewery’s processes including ASi Masters and motors are controlled via PROFINET by two Siemens PLCs. All the tanks, kettles and plant components can be mutually connected by means of a system of 744 pneumatically activated process valves – controlled by eight ASi Masters from Bihl+Wiedemann. The ASi network also links together instruments and sensors that record the process data from each fermentation tank, such as the pressure, level and temperature.


Video-Lenghts: 2:45

Overview of ASi Benefits

  • Simple, low-cost commissioning
  • Just one cable for data and power
  • Noise-immune – ideal for safety-relevant equipment
  • Cost-saving
  • System- and manufacturer-neutral
  • Simple to configure and expand
  • Free topology – each slave can be located at any desired point

Questions about our products and solutions?