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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 AS-i 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 AS-i cable. This cable carries both data and power.

The four AS-i 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 AS-i 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 AS-i 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: AS-i 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

AS-i 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 27 million active AS-i devices worldwide
  • Three million of these are safety devices

  • Over 1.800 certified products
  • Safety relevant units with around 70% growth rate

Components of the AS-i Network

AS-Interface Master

connects sensors and actuators through the AS-i 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 AS-i network with 30 volts.




Factory Automation


Vehicle Automation

Process Automation

Overview of AS-i 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?