The Actuator-Sensor Actuator-Sensor Interface is used in the lowest end of industrial data communication. Main areas of use are the connection of binary actuators and sensors. The Actuator-Sensor Actuator-Sensor Interface is normed according to EN 50295 and is a manufacturer-independent manufacturer-independent bus system of the degree of protection IP67.
Properties
SITRAIN Training for Automation and Drives
Connectable system:
binary inputs and outputs analog inputs and outputs
Number of slaves:
maximum of 62
Response time:
< 5ms
Maximum length:
300 m
Topologies:
Point to Point topology Star topology Bus topology
Transport medium:
unshielded cable with 2 wires
Bus principle:
Master - Slave
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ST-PRO1 AS-i Communications Communications System
AS-i Cabl e
Geometrical ribbon cable
Contacts
SIMATIC S7 Siemens AG 2004. All rights reserved.
Energy and Data
Date: File:
24.06.2004 PRO1_A1E.3
Slave housi ng
SITRAIN Training for Automation and Drives
AS-interface AS-interface uses unshielded ribbon cable to transmit transmit data and energy (IP67). (IP67). This cable is yellow. Because of the transmission of data and energy on a two-wire cable, a special AS-i – power pack with data isolation is required. required.
Properties
Due to the geometric geometric design of the cable, the the wires for + and – can no longer be mixed up. The cable is “self-healing”. Slaves can be placed where ever you like.
Au xi li ary Po wer
For power consumption over 8 amperes or for selective switch-off, such as, in emergency situations, an AC or DC auxiliary power can can be laid in parallel through a cable of the same kind. Typically, a red cable cable is used for 230 VAC and a black cable is used for 24 VDC.
SITRAIN Training for Automation and Drives
Page age 3
ST-PRO1 AS-i Communications Communications System
AS-i Modul Mod ul es
AS-i Bu s Compact Modules Profibus DP
An alo g Modu Mo du les DP/AS-i DP/AS-i Li nk 20
Power Supply
SIMATIC S7 Siemens AG 2004. All rights reserved.
DP/ASDP/AS-ii L ink 20
Date: File:
24.06.2004 PRO1_A1E.4
SITRAIN Training for Automation and Drives
The DP/AS-i Link 20 takes over the role of AS-i Master and is Profibus slave with regards to its connection to the SIMATIC S7 at the same time. Through communication communication processors (CP), the the SIMATIC S7 S7 could also be connected directly with the AS-i bus.
Slaves
Every AS-i slave has a unique bus address. You enter this bus address with the programming unit.
Compact Modules
Compact modules consist consist of two housing parts: parts: the mounting plate plate (base module) and the attach attach module (communication (communication unit). The mounting plate makes the connection with the yellow As-i cable and is snapped onto a commercial DIN mounting mounting rail. The standard actuators actuators and sensors are attached to the attach module with screw caps. There are atttach modules with up to a maximum of 4 inputs and 4 outputs each.
An alo g Mo du les
The design of the analog modules i s the same as for the compact modules. Analog modules can have a maximum maximum of 2 channels. channels. These can be 2 input or 2 or 2 output channels. Analog sensors are also connected with screw caps.
SITRAIN Training for Automation and Drives
Page age 4
ST-PRO1 AS-i Communications Communications System
Configuration
Profibus Slave AS-i Mast er
SIMATIC S7 Siemens AG 2004. All rights reserved.
Date: File:
24.06.2004 PRO1_A1E.5
SITRAIN Training for Automation and Drives
Configuration
The DP/ASI-i Link 20 is used in the hardware configuration like a standard Profibus slave.
Ad dr ess es
The DP/AS-i Link 20 is given a Profibus DP slave address, such as, the address 100. After that, that, 16 input bytes and 16 output bytes each are assigned. assigned. In the example, these are the the addresses 24 to 39 – for the inputs as well as for the the outputs.
Communication
SITRAIN Training for Automation and Drives
The Profibus master communicates with the DP/AS-i Link 20 as Profibus slave through the assigned input and output areas. The DP/AS-i Link 20 communicates independently independently as AS-i master with a maximum of 62 slaves.
For every slave, 4 bits for inputs and outputs are always reserved (see also above slide). Depending of the type of AS-i slave, all or some of the bits are needed for communication.
