Fail-safe Controllers

Engineering

Integrated engineering for safety-oriented and standard programs

Safety-oriented and standard programs not only run on one and the same CPU, they can also be created using the same engineering tools.

The safety-oriented program part is created using the standard LAD and FBD STEP 7 languages and the S7 Distributed Safety option package. To simplify programming, the latter contains a command library with TÜV-approved software blocks (e.g. EMERGENCY-OFF, two-hand control, muting, gate monitoring). Users can also create their own blocks. This

considerably simplifies reproducibility and/or extension of existing projects.

Two optional F Libraries for burner management include certified blocks for

• industrial gas and oil burner acc. to IEC 61508, SIL 3 and TRD-Standards 411, 412 ( Manual,  Demo project,  Short infos)
• implementation of safety press functions, certified ace. EN 954-1 Category 4 and IEC 61508.

During generation of the safety-oriented program, the S7 Distributed Safety package performs automatic safety checks and links in additional safety blocks for error recognition and handling. These control blocks ensure that software errors and hardware faults are recognized and that corresponding reactions occur, which keep the safety system in a safe state or switch it to a safe state. In addition the S7 Distributed Safety package supports a comparison of safety programs and acceptance test of the plant using the generated program printout.