• Password protection;
  a password concept protects the user program from unauthorized access.
• Diagnostics buffer;
  the last 500 errors and interrupt events are saved in a buffer for diagnostics purposes.
• Maintenance-free data back-up;
  all standard data is automatically written onto the SIMATIC Micro Memory Card by the CPU if there is a voltage interruption, and is available unchanged following voltage recovery.

Parameterizable properties

The S7 configuration as well as the properties and response of the CPUs can be parameterized using STEP 7:

• MPI multipoint interface;
  determining station addresses
• Restart/cycle time behavior;
  stipulation of maximum cycle time and loading as well as self-test functions
• Clock bit memory;
  setting of addresses
• Protection level;
  specifying the access rights to program and data
• System diagnostics;
  determining handling and scope of the diagnostic alarms
• Watchdog interrupts;
  setting of periodicity
• Clock interrupts;
  setting of start date, start time and periodicity
• PROFIBUS DP master/slave interface;
  user-defined address assignment for distributed I/O

Information and display functions

• Status and error indications;
  LEDs indicate hardware, programming, time or I/O errors, and operating statuses such as RUN, STOP and start-up.
• Test functions;
  the PG is used to indicate signal status during program execution, to modify process variables independently of the user program and to output the contents of stack memories.
• Information functions;
  you can use the PG to obtain information about the storage capacity and operating mode of the CPU as well as the current loading of the main and load memories as well as current cycle times and diagnostic buffer contents in plain text.

Integrated communication functions

• PG/OP communication
• Global data communication
• S7 basic communication
• S7 communication (server only)
• Routing
• Data record routing

Communication

The safety-related and standard communication between the central controller and the distributed stations is performed via PROFIBUS DP. The specially developed PROFIBUS profile PROFIsafe supports the transfer of user data for the safety functions within the standard data message frame. Additional hardware components, e.g. special safety buses are not required. The necessary software is either integrated in the hardware components as an expansion of the operating system or loaded into the CPU later as a certified software block.

System functions

The CPU provides many extensive system functions for diagnostics, parameterization, synchronization, alerting, time measurement, etc.
For further details, see the manual.

Mode of operation

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

The signal modules monitor the output and input signals by means of discrepancy analysis and the injection of test signals.

The CPU checks the proper operation of the controller by means of periodic self-tests, command tests and logic-based and time-based program execution checks. Furthermore, the I/O is checked using requests for signs of life.

If an error is diagnosed in the system, the system will be placed in a safe state.

An F runtime license is not required for operating the S7-300F-2 DP.

Programming

The CPU 315F-2 DP is programmed in the same manner as other SIMATIC S7 systems. The user program for non-fail-safe plant sections is created using familiar programming tools, e.g. STEP 7.

Option packages SIMATIC S7 Distributed Safety (Classic) and SIMATIC Safety Advanced V12 (TIA Portal V12)

The STEP 7 option packages "SIMATIC S7 Distributed Safety" (Classic) or SIMATIC Safety Advanced V12 (TIA Portal V12) are required for programming the safety-related program sections. The package contains all the functions and blocks required to create an F program.

The F program with the safety functions is created in F-FBD or F-LAD or using special function blocks from the F library. Use of F FBD or F LAD simplifies configuration and programming of the plant and also acceptance testing thanks to the non-plant-specific uniform presentation form. The programmer can concentrate on configuration of the safety-related application without the need to use additional tools.