• Password protection;
  a password concept protects the user program from unauthorized access.
• Diagnostics buffer;
  the last 100 error and interrupt events are stored in a buffer for diagnostic purposes.
• Maintenance-free data backup;
  all data is automatically backed up by the CPU if the voltage is interrupted and is available unchanged after the voltage has been reconnected.

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
• 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-oriented address assignment for distributed I/O

Information and display functions

• Status and error indications;
  LEDs indicate e.g. hardware, programming, time, I/O or bus errors, as well as operating states such as RUN, STOP and restart.
• 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;
  the PG can be used to obtain information about the memory capacity and operating mode of the CPU, the current loading of the work and load memory, current cycle times and diagnostics buffer content in plain text.

Integrated communication functions

• PG/OP communication
• Global data communication
• S7 basic communication
• S7 communication (server only)

System functions

The CPU provides many extensive system functions for diagnostics, parameterization, synchronization, alerting, time measurement, etc.
See Manual for details.

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 allows the transmission of user data associated with the safety function within the standard data telegram. 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.

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 operation of the CPU 317F-2 DP.

Programming

The CPU 317F-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 packages contain all the functions and blocks required to create an F program.

The F program with the safety functions is connected in F FBD or F LAD or using special functions 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.