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Control of Fire Dampers and Smoke Extraction Dampers

AS-Interface – Building Automation

The advantages of AS-Interface – such as simple, cost-saving installation and high degree of flexibility – have now become familiar in building automation as well. Numerous companies are relying on the ASi installation system for applications such as controlling fire and smoke damper systems, shutter drives or heating and cooling ceilings using analog output modules. Damper actuators with flow regulators can also be connected to the controller through the MP-Bus Gateway. It is also possible to process EnOcean signals from wireless buttons and sensors through ASi. Customer proximity is our hallmark, which means we stand by you in word and deed and are open to custom-tailored solutions. Just contact us.

Free Topology

ASi supports free topology such as Tree-, Ring, Linear and Star network.

Tree topology

Ring topology

Low costs

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


High availability and safety in accordance with SIL – problem free

AS-Interface also enables safety-relevant systems (EN ISO 13849) to be equipped with interference protection. High-availability or redundant systems (even with circuit integrity) and systems with special safety requirements, such as SIL1, SIL2 or SIL3, all fall under the application spectrum of ASi. The cabling route and communication with all participants are constantly monitored, even in the standard version. This ensures that all dampers can be still controlled in the event of a fire.


Installation – very simple

  • AS-Interface provides a clever connection technology over a profiled cable. Lay the cable, screw on tightly, ready. Contact pins always penetrate vertically into the profile cable to guarantee optimal contacting
  • Optimal contacting provided by:
    • Vertical contacting
    • 4 or 6 pins per cable and 2 or 3 pins per conductor

ASi Features per Line

Standardized System

EN 50295, IEC 62026-2


Unshielded two conductor profile cable


Power Supply and data in one cable with max. 8 A

Cable Length

100 m (extensible up to 1000 m)

Number of Nodes per ASi Network

Up to 62

Number of I/O Binary

Up to 248 Inputs and 248 Outputs

Number of I/O Analog

Up to 124 Inputs or Outputs

Cycle Time

5 ms

Supported Topology

Tree, linear, star


up to SIL 3, Category 4, PLe (EN 62061, EN 61508, EN ISO 13849-1, EN 954-1)

Connection to any Building Management System

Safety in case of fire

Pre-wired and configured stand alone control for fire dampers


Gateways for linking to any Building Management System

Option: can be used with integrated controller (mini-PLC) or as stand-alone device

  • Permanent cable route monitoring
  • Plain text messages on the display and to the BMS
  • Also available as pre-configured

Field Modules

Module for controlling damper actuators

Relay module to control motor driven 230 V damper actuators

Module for detecting the end positions of thermal fire dampers

  • 4I module
  • AB address  (up to 62 nodes)
  • Supply of inputs via ASi
  • Housing with external fastening tabs

Control Cabinet Modules

In Stainless Steel, IP20

  • Digital 4I/4O
  • Digital 8I
  • Digital 8O
  • Relay outputs (230 V AC)

Cabinet modules

  • 4I/4O, 8I/8O
  • 0/4...20m A
  • 0...10 V
  • Pt100/Pt1000
  • Thermocouples
  • Relay


  • Optional with integrated bus termination
  • Also available in IP65

Power Supplies

  • Single Phase
  • 3 Phases
  • 24 V to ASi
  • 1,8 A, 2 A, 4 A, 8 A
  • Decoupling unit for 2 ASi networks

Profile and round cable

It is possible to use a specific cable for various applications. For instance, the profile cable with polarity reversal protection is suitable for fire dampers. It is halogen-free and available in 1.5 mm2 or 2.5 mm2. However, it may also be possible to use a pre-laid round cable, such as NYM 2 × 1.5 mm2 or NYM 2 × 2.5 mm2. In terms of smoke extraction, cables with circuit integrity (e.g. E90) are often necessary.


Commissioning / Diagnostic / Software / Test Run

The ASi masters can transfer all data to a higher level control or process them locally depending on the application and their requirements. In terms of local processing, they offer maximum flexibility, and they are freely programmable or provided complete with a pre-installed program for many application scenarios: connect - ready. Of course, all state information and diagnostic messages from the building control system are always available. An integrated web server enables remote diagnostics even from computers without diagnostics software.


The comprehensive package is rounded off by comfortable tools for commissioning, diagnostics and test runs.

This could also be of interest to you

Building automation with ASi

Learn more about simple and cost-saving installation of ASi in building automation. For example, to control fire and smoke dampers, blind drives or heating/cooling ceilings.


The standardized fieldbus system AS-Interface (ASi) helps you drastically reduce your wiring complexity. You also benefit from free choice of topology and cost-effective integration of safety features on the same infrastructure.

Products for Building Automation Available in the Web Shop

ASi advantages, such as freedom of topology, extremely simple installation or high flexibility, have also become widely adopted in building services engineering. Here you will find our wide range of products.

Questions about our products and solutions?