Actuator Sensor-Interface (AS-Interface)

AS-Interface was designed as a simple system for the quick data exchange of binary signals.  An international standard since 1999, in  accordance with EN 50295 and IEC 62026-2.

Quick and Uncomplicated

The biggest advantage of AS-Interface is the quick and uncomplicated installation of the  system. Communication (Manchester Encoding) and power are transmitted via a 2-wire cable. By using piercing technology for contacting to the cable it is possible to insert a new slave  at any point in the system. In addition, the arbitrary structure of the bus (line, tree,  star, ...) permits the perfect adaptation to the plant or machine. AS-Interface is mainly used for small machines, as a subsystem for more complex bus systems (e.g. PROFIBUS-DP) or as an easy introduction to bus technology.

General Technical Data

Transmission medium

• Unshielded 2-wire cable for power supply (module electronics and sensors) and data transmission (Manchester Encoding)

• Optional mechanically encoded flat or round cable

Network topology

The bus can be built arbitrarily (line, star, tree, ...). Terminating resistors are not required.

Number of devices

• 31 slaves by using standard slaves

• 62 slaves by using A/B slaves with profile 3.0

Reliable transmission rates and segment lengths

• Transmission rate: 167 kBaud

• Max. segment length: 100 m

Addressing

AS-Interface slaves are generally addressed via software (the default address is generally “0” for all AS-Interface slaves).

This can be done in several ways:

• Via the master: The slaves are connected to the master consecutively. The latter automatically identifies the kind of slave and builds up a communication. Then the slave can be addressed.

• Via an addressing unit: All AS-Interface slaves can be addressed with the standard addressing unit “0913 ATL 003”.

• Automatic addressing: If a slave in a network fails, AS-Interface offers the chance of auto-addressing. The defective slave is replaced by an identical one. The master identifies this slave and automatically addresses it to the address of the missing slave