S7-300

S7-300

• The modular mini PLC system for the low and mid-performance ranges
• With comprehensive range of modules for optimum adaptation to the automation task
• Flexible use through simple implementation of distributed structures and versatile networking
• User-friendly handling and uncomplicated design without a fan
• Can be expanded without problems when the tasks increase
• High performance thanks to a range of integrated functions

S7-300F

• Fail-safe automation system for plants with increased safety requirements for production technology
• Based on S7-300
• Additional ET 200S and ET 200M distributed I/O devices complete with safety-related modules can be connected
• Safety-related communication via PROFIBUS DP with PROFIsafe profile
• Standard modules can be used in addition for non-safety-oriented applications

Availability

As part of our established product portfolio, the SIMATIC S7-300/ET 200M system families will generally be available until 2023.
Following the product phase-out declaration, products will be available as spare parts for another ten years.

Catalog ST 70:

You can also find information about SIMATIC S7-300 in Catalog ST 70 under this link.

S7-300

SIMATIC S7-300 is the mini PLC system for the lower and medium performance ranges.

The modular and fan-free design, simple implementation of distributed structures, and convenient handling make the SIMATIC S7-300 the cost-effective and user-friendly solution for the most diverse tasks in the low-end and mid performance ranges.

Application areas of the SIMATIC S7-300 include:

• Special machinery
• Textile machines
• Packaging machinery
• General mechanical equipment manufacture
• Controller building
• Machine tool manufacture
• Installation systems
• Electrical/electronics industry and the skilled trades

Several performance-graded CPUs and a comprehensive range of modules with a host of user-friendly functions allow you to use only those modules necessary for your application. In the case of task expansions, the controller can be upgraded at any time by means of additional modules.

SIMATIC S7-300 can be used universally:

• Maximum suitability for industry thanks to high electromagnetic compatibility and high resistance to shock and vibration.
  

S7-300F

The SIMATIC S7-300F fail-safe automation system is used in plants with increased safety requirements. It controls processes where immediate shutdown presents no danger to personnel or the environment.

S7-300F complies with the following safety requirements:

• Requirement class AK 1 to AK 6 in accordance with DIN V 19250/DIN V VDE 0801
• Safety requirement class SIL 1 to SIL 3 in accordance with IEC 61508
• Category 1 to 4 in accordance with EN 954-1

Additionally, standard modules may also be used in S7-300F alongside the fail-safe modules. This makes it possible to establish a fully integrated control system for a plant where non-safety related tasks and safety-related tasks co-exist. The overall plant is configured and programmed with the same standard tools.

S7-300

General

The S7-300 automation system is modular in design. It has a comprehensive range of modules that can be combined individually.

A system includes the following:

• A CPU:
  Different CPUs are available for different performance ranges, including CPUs with integral inputs/outputs and the corresponding functions, as well as CPUs with integral PROFIBUS DP, PROFINET and point-to-point interfaces.
• Signal modules (SMs) for digital and analog inputs/outputs.
• Communications processors (CPs) for bus connection and point-to-point connections.
• Function modules (FMs) for high-speed counting, positioning (open-loop/closed-loop) and PID control.

The following can also be used depending on requirements:

• Load current supplies (PS) for the connection of SIMATIC S7-300 to a 120/230 V AC supply voltage.
• Interface modules (IMs) for connecting the central controller (CC) and expansion units (EUs) in multi-tier configurations.
  SIMATIC S7-300 can be operated with up to 32 modules distributed across the CC and 3 EUs. All modules can be operated in enclosures and without fans.
• SIPLUS modules for extended environmental conditions:
  suitable for temperature range -25 to +60 °C, and higher humidity, condensation and frost loads. Can be used direct on vehicles or outside building in an IP20 cabinet protected against direct sunlight and rainwater/spray water. Air-conditioned cabinet and IP65 housing not required.

Design

The simple design makes the S7-300 versatile and easy to maintain:

• Module mounting:
  Simply hang the modules on the mounting rail, swing them into place and screw into position.
• Integrated backplane bus:
  The backplane bus is integrated into the modules. The modules are connected via bus connectors plugged into the rear of the housings.
• Simple replacement of the modules with mechanical key coding:
  Only the fixing screw of the modules has to be unscrewed to replace the module. Wired front connectors are easy to release by pressing on the locking mechanism. The front connector coding prevents connection of the wired front connector to the wrong module type.
• Field-proven connections:
  Screw-type, spring-loaded or insulation-displacement front connectors are offered for the signal modules.
• TOP Connect:
  This offers pre-assembled wiring with 1-core to 3-core connections and screw-type or spring-loaded terminals. Alternative to wiring direct on the signal module.
• Defined installation depth:
  All connections and connectors are recessed into the modules and protected and covered by front doors. All modules thus have a defined installation depth.
• No slot rules:
  Signal modules and communications processors can be connected in any way without restrictions. The system configures itself.

Expansion

Should the user require more than 8 slots for SM, FM or CP modules for his or her automation tasks, the S7-300 (with the exception of CPU 312 and CPU 312C) can be expanded:

• Max. 32 modules on CC and 3 EUs:
  In total, a maximum of 3 expansion units (EUs) can be connected to the central controller (CC). Eight modules can be connected to each CC/EU.
• Connection via interface modules:
  Each CC/EU has its own interface module. It is always plugged into the slot next to the CPU on the CC and handles communication with the EUs autonomously.
  
  • Expansion via IM 365:
    1 EU, distance max. 1 m; supply voltage is also transferred.
  • Expansion via IM 360/361:
    3 EUs, max. distance between CC and EU and between EU and EU, 10 m in each case.
• Physically separate installation:
  The individual CCs/EUs can also be installed at greater distances from each other. Distance between two neighboring CC/EU or EU/EU: max. 10 m.
• Flexible mounting options:
  The CCs/EUs can be mounted horizontally or vertically. They can thus adapt optimally to the available space.

Communication

S7-300 has different communication interfaces:

• Communications processors for connecting to the bus systems AS-Interface, PROFIBUS and PROFINET/Industrial Ethernet.
• Communication modules for point-to-point connections.
• Multipoint interface (MPI), integrated into the CPU;
  the low-cost solution for simultaneous connection of PGs/PCs, HMI systems and other SIMATIC S7/C7 automation systems.

Process communication via PROFIBUS DP

The SIMATIC S7-300 is connected to the PROFIBUS DP bus system via a communications module or via the CPUs with integral PROFIBUS DP interfaces. The CPUs with PROFIBUS DP master/slave interface enable distributed automation configurations with high speed and simple handling.

The distributed I/O via PROFIBUS DP is treated just like a centralized I/O from the user's perspective (same configuring, addressing and programming).

The following can be connected as masters:

• SIMATIC S7-300
  (via CPUs with PROFIBUS DP interface or PROFIBUS DP CPs)
• SIMATIC S7-400
  (via CPUs with PROFIBUS DP interface or PROFIBUS DP CPs)
• SIMATIC C7
  (via C7 with PROFIBUS DP interface or PROFIBUS DP CPs)
• SIMATIC S5-115U/H, S5-135U and S5-155U/H with IM 308
• SIMATIC 505

For performance reasons, no more than 2 masters must be connected on one line.

The following can be connected as slaves:

• ET 200 distributed I/O devices
• S7-300 via CP 342-5
• CPU 313C-2 DP, CPU 314C-2 DP, CPU 314C-2 PN/DP, CPU 315-2 DP, CPU 315-2 PN/DP, CPU 317-2 DP, CPU 317-2 PN/DP and CPU 319-3 PN/DP
• C7-633/P DP, C7-633 DP, C7-634/P DP, C7-634 DP, C7-626 DP, C7-635, C7-636
• Field devices

Although PG/PCs with STEP 7 or OPs are masters on the bus, they only use the MPI functions that also run in part via PROFIBUS DP.

Process communication via PROFINET IO

SIMATIC S7-300 is connected to the PROFINET IO bus system via a communications module or the CPUs with integral PROFINET interfaces. The CPUs with PROFINET interface enable distributed automation configurations with high speed and simple handling.

The distributed I/O via PROFINET IO is treated just like a centralized I/O from the user's perspective (same configuring, addressing, and programming).

The following can be connected as IO controllers:

• SIMATIC S7-300
  (via CPUs with PROFINET interface or PROFINET CPs)
• SIMATIC ET 200
  (via CPUs with PROFINET interface)
• SIMATIC S7-400
  (via CPUs with PROFINET interface or PROFINET CPs)

The following can be connected as IO devices:

• ET 200 distributed I/O devices
• ET 200S IM151-8 PN/DP CPU, ET 200pro IM154-8 PN/DP CPU
• SIMATIC S7-300
  (via CPUs with PROFINET interface or PROFINET CPs)
• Field devices

Process communication via AS-Interface

S7-300 features a communications module (CP 342-2) suitable for connecting field devices (AS-Interface slaves) for the AS-Interface bus.

For additional information, see Communications processors.

Data communication via CP or integral interface (point-to-point)

Point-to-point connections can be conveniently and at low cost via the CP 340/CP 341 communications processors or the integral interface of the CPU 313C-2 PtP or CPU 314C-2 PtP. Different protocols with the three physical transmission media are available:

• 20 mA (TTY) (CP 340/CP 341 only)
• RS 232C/V.24 (CP 340/CP 341 only)
• RS 422/RS 485

The following can be connected:

• SIMATIC S7 and SIMATIC S5 automation systems and non-Siemens systems
• Printers
• Robot controls
• Scanners, barcode readers, etc.

Special blocks are included in the scope of supply of the manuals for the communication functions.

Data communication via multipoint interface (MPI)

The MPI (Multi Point Interface) is a communications interface integrated in the SIMATIC S7-300-CPUs. It can be used for simple networking.

• The MPI enables simultaneous connection of several PGs/PCs with STEP 7, HMI systems (OP/OS), S7-300 and S7-400.
• Global data:
  With the "Global data communication" service, networked CPUs can exchange data with each other cyclically. An S7-300 CPU can exchange up to 4 packets of 22 bytes each, with a maximum of 16 CPUs participating in the data exchange (with STEP 7 V4.x).
  This allows, for example, one CPU to access the inputs/outputs of another CPU. Global data communication can only take place via the MPI interface.
• Internal communication bus (C bus):
  The MPI of the CPU is connected directly with the C bus of the S7-300. FM/CP modules with C bus connection can thus be addressed direct from the PG via the MPI.
• Powerful communications technology:
  
  • Up to 32 MPI nodes.
  • Several communication connections per CPU for S7 basic communication with the SIMATIC S7-300/-400.
  • Several communication connections per CPU for S7 communication with PGs/PCs, SIMATIC HMI systems, and the SIMATIC S7-300/400.
  • Data transfer rate 187.5 kbit/s or 12 Mbit/s
• Flexible configuration options:
  Field-proven components are used to establish MPI communication: Bus cable, bus connectors and RS 485 repeaters from the PROFIBUS and "distributed I/O" ranges. They enable optimal adaptation of the design to the requirements. For example, up to 10 repeaters can be switched in series to bridge larger distances between any two MPI nodes.

Data communication via CP

SIMATIC S7-300 can be connected to the PROFIBUS and Industrial Ethernet bus systems via the CP 342 and CP 343 communications modules.

The following can be connected:

• SIMATIC S7-300
• SIMATIC S7-400
• SIMATIC S5-115U/H, S5-135U, S5-155U/H
• Programming devices
• Personal computers
• SIMATIC HMI human machine interface systems
• Numerical controls
• Robot controls
• Industrial PCs
• Drive controls
• Devices of other manufacturers

S7-300F

S7-300F can be operated with two I/O designs:

• Design with I/O in ET 200M:
  Fail-safe digital/analog input and output modules for centralized or distributed use (Cat.4/SIL3 only in conjunction with isolating module).
• Design with I/O in ET 200S PROFIsafe:
  Fail-safe digital input and output modules for distributed use

S7-300

A host of features support users in the programming, commissioning and servicing of the S7-300.

• High-speed instruction processing:
  Instruction execution times from 4 ns open up completely new application options in the low-end and mid performance range.
• Floating-point arithmetic:
  With floating-point arithmetic, even complex arithmetic functions can be used effectively.
• User-friendly parameter assignment:
  There is only one single software tool with a uniform operator interface for parameterizing all modules. This saves on induction and training overhead.
• Operator control and monitoring (HMI):
  User-friendly HMI services are already integrated into the S7-300 operating system. Costly programming of these functions is no longer necessary: The SIMATIC HMI system requests process data from SIMATIC S7-300—the S7-300 operating system transfers this data automatically at the desired update times. And all with uniform symbols and database.
• Diagnostic functions:
  The intelligent diagnostics system of the CPUs continuously checks the functionality of the system and registers errors and specific system events (e.g. time errors, module failures, etc.) The events are saved in a ring buffer and tagged with a time stamp for future troubleshooting.
• Password protection:
  Password protection allows users to protect their know-how effectively against unauthorized copying and modification.

The SIMATIC S7-300 complies with national and international standards:

• CE marking
• UL approval
• CSA approval
• cULus approval
• cULus HAZ.LOC. approval
• FM approval
• ATEX approval
• Marking for Australia
• IEC 61131
• Marine approval
  
  • ABS (American Bureau of Shipping)
  • BV (Bureau Veritas - French marine classification society)
  • DNV (Det Norske Veritas)
  • GL (Germanischer Lloyd)
  • LRS (Lloyds Register of Shipping)
  • Class NK (Nippon Kaiji Kyokai)

For details, refer to Manual "SIMATIC S7-300 Programmable Controller S7-300 Module Data" under "1. General technical data / 1.1 Standards and approvals".

Communication

The SIMATIC S7-300-CPUs support the following communication types:

• Process communication:
  For cyclic addressing of I/O modules (exchange of the process image) via a bus (AS-Interface, PROFIBUS DP or PROFINET). Process communication is called up from the cyclic execution levels.
• Data communication:
  For data exchange between automation systems or between HMI stations and several automation systems. Data communication takes place cyclically or it is called from the user program via blocks on an event-driven basis.

The user-friendly STEP 7 operator interface that significantly simplifies configuring is available to users for configuring the communication functions.

Data communication

SIMATIC S7-300 supports different data communication mechanisms:

• Cyclic exchange of data packets between CPUs networked via MPI with global data communication.
• Event-driven communication with other partners with the communication functions. Networking can take place via MPI, PROFIBUS or PROFINET.

Global data

With the "Global data communication" service, networked CPUs can exchange data with each other cyclically (max. 8 GD packets with 22 bytes each per cycle). This allows, for example, one CPU to access the data, bit memories and process image of another CPU. Global data communication can only take place via the MPI. Configuring is carried out using the GD table in STEP 7.

Communication functions

Communications services with S7/C7 partners can be established with system-integrated blocks.

The services are:

• S7 basic communication via MPI.
• S7 communication via MPI, C bus, PROFIBUS and PROFINET/Industrial Ethernet.
  S7-300 can be used:
  • As a server via MPI, C bus and PROFIBUS
  • As a server or client via the integral PROFINET interface

Communications services with S5 partners and non-Siemens devices can be established with reloadable blocks.

The services are:

• S5-compatible communication via PROFIBUS and Industrial Ethernet
• Standard communication (non-Siemens systems) via PROFIBUS and Industrial Ethernet

In contrast to global data, communication connections must be set up for the communication functions.

Integration into the IT world

With SIMATIC S7-300 it is possible to simply link the modern IT world with automation engineering. The following IT functions are possible via the CP 343-1 Advanced:

• IP routing;
  forwarding of IP V4 messages from the Gigabit to the PROFINET interface controlled via the IP access list
• WEB server;
  up to 30 MB of freely definable HTML web pages can be called up via a standard web browser; data handling of your own file system via FTP
• Standard diagnostics pages;
  for high-speed diagnostics in the plant for all modules plugged into the mounting rack, without additional tool
• Email;
  Sending email with authentication direct from the user program. The email client function makes it possible to alert users direct from the control program
• Communication via FTP;
  open protocol available on most operating system platforms
• The 30 MB RAM file system can be used for intermediate storage of dynamic data.

The S7-300 PROFINET CPUs have an integral Web server. Information can thus be read out of the S7-300 station using a standard Web browser:

• General CPU information
• Content of the diagnostic buffer
• Variable table
• Tag status
• Module status
• Alarms
• Information on Industrial Ethernet
• Topology of the PROFINET nodes

Via the user-defined pages, write access via the Web server to the S7-300 CPU is also possible.

Isochronous mode

The system function isochronous mode enables synchronous coupling

• of the distributed signal acquisition,
• the signal transmission via PROFIBUS/PROFINET and
• the program execution

for the PROFIBUS/PROFINET constant bus cycle time.

An automation solution is created that captures and processes the input signals and outputs output signals at constant intervals (constant bus cycle time). A consistent process image partition is created at the same time.

S7-300 ensures precisely reproducible and defined process response times by means of constant bus cycle times and synchronous signal processing of the distributed I/O.

An extensive range of components that support the isochronous mode system function is available for handling demanding tasks from the areas of Motion Control, measured value acquisition, high-speed controls, etc.

In distributed automation solutions, SIMATIC S7-300 can open up the important application area of high-speed processing operations to enable maximum precision and reproducibility. This means increased production with optimal and constant quality.

Diagnostics and process monitoring of modules

Many SIMATIC S7-300 input/output modules feature intelligent capabilities:

• Monitoring of signal acquisition (diagnostics)
• Monitoring of signals from the process (hardware interrupt)

Diagnostics

Diagnostics can be used to determine whether signal acquisition (in the case of digital modules) or analog processing (analog modules) of the module is functioning fault-free. In diagnostics analysis, a distinction must be made between parameterizable and non-parameterizable diagnostics messages:

• Parameterizable diagnostics messages:
  The diagnostics message is only sent if it has been enabled by the appropriate parameterization.
• Non-parameterizable diagnostics messages:
  These messages are sent as a matter of course, that is, independently of parameterization.

If a diagnostics message is active (e.g. "No sensor supply"), the module triggers a diagnostics interrupt (if the diagnostics message is parameterized, only after the appropriate parameterization). The CPU interrupts processing of the user program or low priority classes, and processes the relevant diagnostics interrupt block (OB 82).

Hardware interrupt

Process signals can be monitored via hardware interrupts and responses to changes in the signals can be triggered.

• Digital input modules:
  Depending on the parameterization, the module can trigger a hardware interrupt for each channel group optionally at a rising edge, a falling edge or at both edges of a signal status change. The CPU interrupts processing of the user program or low priority classes, and processes the relevant diagnostics interrupt block (OB 40). The signal module can buffer one interrupt per channel.
• Analog input modules:
  A working range is defined by parameterizing a high and low limit value. The module compares the digitized measured value with these limits. If the measured value violates one of these limits, a hardware interrupt is triggered. The CPU interrupts processing of the user program or low priority classes, and processes the relevant diagnostics interrupt block (OB 40). If the limits are above/below the overrange/underrange, no comparison is made.
  

S7-300F

Mode of operation

The S7-300F safety functions are contained in the F program of the CPU and in the fail-safe signal modules.

The signal modules monitor output and input signals by means of discrepancy analyses and test signal injections.

The CPU checks the proper operation of the controller with regular self-tests, command tests, and logical and chronological program execution checks. In addition, the I/O is checked by means of sign-of-life requests.

If a fault is diagnosed in the system, the system is brought to a safe state.

Programming

The safety-related programs for the CPU 315F are programmed with the STEP 7 languages LAD and FBD. The scope of functions with regard to operations and data types is restricted here. A safety-related program is created by making special specifications at the compiling stage. As well as the fail-safe program, a standard program can also run in parallel on one CPU (coexistence) with no restrictions.

An additional component part of this software package is the F library with off-the-shelf, TÜV-accepted programming examples for safety-related functions. These programming examples can be modified but the modifications must be re-certified.

S7 F Distributed Safety option package

The option package "S7 F Distributed Safety" is required for programming the safety-related program sections. The package contains all the necessary functions and blocks for creating the F program. STEP 7 from V5.1SP3 must be installed for S7 F Distributed Safety to run.