SIEMENS
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Siemens D 31 · 2015
2
Highlights
Communication
> AS-Interface
■
Overview
AS-Interface serves as a cost-effective system for the lower field
level of automation. AS-Interface was specially developed to
meet the demands of connecting binary sensors and actuators
as well as interfacing to the higher control level. A straightfor-
ward, cost-effective installation with minimal connection costs
was of paramount importance to the developers. The AS-Inter-
face is often used in systems where numerous actuators and
sensors, installed across a wide area,
need to be networked
cost effectively. Examples include conveyor and handling sys-
tems in airports, automated postal sorting, and the food and
beverage industry.
■
Overview
As simple fieldbus protocols, USS (
U
niversal
S
erial
I
nterface
protocol of Siemens AG, 1992) and Modbus RTU can be used
both cyclically and acyclically. Based on RS485 physical bus
characteristics, up to 32 nodes can be networked to one bus
segment and connected to a higher-level controller. These
protocols are used when there are limited demands on data
throughput.
■
Overview
BACnet MS/TP (
B
uilding
A
utomation and
C
ontrol
Net
works
M
aster-
S
lave/
T
oken
P
assing) is another fieldbus system based
on RS485 physical characteristics, which is mainly used in the
field of building automation. BACnet MS/TP defines a variety of
services including data utilization, alarm processing, event
handling, processing of value changes, device and network
management as well as various types of objects. Interoperability
is ensured by means of a uniform approach to services and
procedures, which is laid down in "application profiles". These
profiles are available for a wide range of applications. The
SINAMICS G120P inverters, especially developed for fluid flow
machines (such as pumps, fans and compressor drives), use
the application profile "BACnet application-specific controller" in
building automation.
■
Overview
CANopen is a communication protocol based on CAN physical
characteristics, which is predominantly used in the automation
industry and for networking within complex devices. Originally
conceived as a fieldbus for networking devices in motion control
applications such as handling systems, CANopen has since
established itself in the field of medical engineering, vehicle
automation, rail and ship networking as well as building auto-
mation. Interoperability of CANopen is ensured through the use
of application and device profiles, whereby the wide range of
options offered by the bus specification enables an appropriate,
precise selection to be made for the application or device in
question. Furthermore, inverters with CANopen support the
"CiA 402 Electrical Drives" device profile.
■
Overview
Ethernet Industrial Protocol (EtherNet/IP) is an open standard for
industrial networks. EtherNet/IP is used to transmit cyclic I/O
data and acyclic parameter data. EtherNet/IP was developed by
Rockwell Automation and the ODVA (Open DeviceNet Vendor
Association), and belongs to the standardized international
standard series IEC 61158. EtherNet/IP is a popular communica-
tion standard, particularly in the American market and in the
Rockwell controllers environment.
Communication
> USS and Modbus RTU
Communication
> BacNet MS/TP
Communication
> CANopen
Communication
> EtherNet/IP
© Siemens AG 2014