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Siemens ST PCS 7 · 2017 (Preliminary edition)
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Automation Systems
Complementary S7-400 systems
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Overview
With the S7-400 automation systems, which are scalable via
different types of CPU, you have an alternative to AS 410 auto-
mation systems. The systems that can be used in plants with
SIMATIC PCS 7 V7/V8 can be classified as follows:
•
Standard automation systems
•
High availability automation systems
•
Safety-related automation systems
Standard automation systems
The AS 414-3, AS 414-3IE, AS 416-2, AS 416-3, AS 416-3IE and
AS 417-4 standard automation systems are extremely robust
and feature high processing and communication performance.
The AS 414-3 and AS 414-3IE are tailored for smaller-scale
applications with smaller quantity structures. This allows for a
low-cost starter solution with a modular and scalable system
based on the S7-400 controller range. Larger quantity frame-
works can be implemented with the AS 416-2, AS416-3/416-3IE
and AS 417-4 automation systems. These systems are preferred
for medium and large-sized plants.
High availability automation systems
The aim in using high availability automation systems is to mini-
mize the risk of a production outage. In accordance with their
basic design, these systems are categorized as:
•
AS Single Stations: AS 412-5-1H, AS 414-5-1H, AS 416-5-1H,
and AS 417-5-1H with only one CPU, e.g. for the following
applications:
- Subsequent expansion to a redundant system
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Redundant configuration on UR1 racks, comprising 2 single
stations, 4 sync modules, and 2 sync fiber-optic cables
•
AS Redundancy Stations: AS 412-5-2H, AS 414-5-2H,
AS 416-5-2H and AS 417-5-2H with two redundant CPUs,
mounted on one common rack (UR2-H) or two separate racks
(UR2)
Safety-related automation systems
Safety-related automation systems (F/FH systems) are available
for safety-relevant applications in which an incident can result in
danger to persons, plant damage or environmental pollution.
These are based on the hardware of the high availability automa-
tion systems, which is expanded by safety functions with
S7 F systems.
In accordance with the design variant, they are categorized as:
•
AS Single Stations
AS 412F, AS 414F, AS 416F, and AS 417F with only one CPU
(safety-related)
•
AS Redundancy Stations
AS 412FH, AS 414FH, AS 416FH, and AS 417FH with two
redundant CPUs (safety-related and high availability)
The safety-related F/FH systems collaborate with safety-related
F modules of the ET 200 distributed I/O systems or fail-safe
transmitters connected directly via the fieldbus to detect not only
faults in the process, but also their own, internal faults. They au-
tomatically transfer the plant to a safe state in the event of a fault.
The redundancy of the FH systems is only used to increase the
availability. It is not relevant to processing of the safety functions
and the associated fault detection.
All F/FH systems are TÜV-certified and comply with the safety
requirements up to SIL 3 according to IEC 61508.
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Design
Racks
Automation systems based on only one CPU (AS Single Station)
can be mounted on a UR1 rack (18 slots) or UR2 rack (9 slots).
The automation systems (AS Redundancy Station) consisting of
two electrically isolated redundant subsystems can be mounted
on a UR2-H compact rack with divided backplane bus or on two
separate racks (UR1 or UR2). The design with two racks allows
physical separation of the redundant subsystems, e.g. by a fire-
proof partition and over a distance of up to 10 km. As a result of
the galvanic isolation, the system is insensitive to electromag-
netic interferences.
Redundant power supply
If you have two separate power supply networks for your system,
you can increase the availability of the automation systems with
redundant power supplies (2 power supplies for one AS Single
Station or 1 or 2 power supplies for each subsystem of an
AS Redundancy Station).
Communication via the Industrial Ethernet (IE) plant bus
Each standard automation system is connected to the
Industrial Ethernet plant bus by means of a CP 443-1 com-
munication module.
If the PN/IE interfaces integrated in the CPUs of the high avail-
ability and safety-related automation systems are not used for
PROFINET IO, they can then also be used for the connection to
the Industrial Ethernet plant bus. Otherwise, the 1H/F systems
(AS Single Station) and the two subsystems of the 2H/FH sys-
tems (AS Redundancy Station) can be connected to the plant
bus via one CP 443-1 communication module each.
I/O connection via PROFIBUS DP
The distributed process I/O can be integrated into a
PROFIBUS DP segment either directly or via a lower-level field-
bus (PROFIBUS PA or FOUNDATION Fieldbus H1).
Several PROFIBUS DP segments with distributed process I/O
can be operated on a standard automation system, an 1H/F sys-
tem (AS Single Station), or a 2H/FH system (AS Redundancy
Station). The following table provides an overview of the number
and type of configurable PROFIBUS DP interfaces.
© Siemens AG 2017