A function block diagram (FBD) is a block diagram that describes a function between input variables and output variables. A function is described as a set of elementary blocks. Input and output variables are connected to blocks by connection lines. An output of a block may also be connected to an input of another block | SIEMENS SIMATIC Preface Contents Fault-Tolerant Programmable Logic Controllers 1 Automation System S7-400H S7-400H Installation Options 2 Fault-tolerant Systems Getting Started 3 Installation of a CPU 41x-H 4 Manual 5 S7-400H in Profibus DP Mode System and Operating Modes of the 6 S7-400H 6 Coupling and Synchronizing 7 Using I O on the S7-400H 8 Communication Functions 9 Configuring with STEP 7 10 Failure and Replacement of 11 Components During Operation Modifying the System During Operation 12 Synchronization modules 13 S7-400 cycle and reaction times 14 Technical Specifications 15 Appendices This manual has the order number 6ES7988-8HA11-8BA0 Glossary Index Edition 04 2005 A5E00267695-02 Safety Guidelines This manual contains notices you have to observe in order to ensure your personal safety as well as to prevent damage to property. The notices referring to your personal safety are highlighted in the manual by a safety alert symbol notices referring to property damage only have no safety alert symbol. The notices shown below are graded according to the degree of danger. Danger indicates that death or severe personal injury will result if proper precautions are not taken. Warning indicates that death or severe personal injury may result if proper precautions are not taken. Caution with a safety alert symbol indicates that minor personal injury can result if proper precautions are not taken. Caution without a safety alert symbol indicates that property damage can result if proper precautions are not taken. Attention indicates that an unintended result or situation can occur if the corresponding notice is not taken into account. If more than one degree of danger is present the warning notice representing the highest degree of danger will be used. A notice warning of injury to persons with a safety alert symbol may also include a warning relating to property damage. Qualified Personnel The device system may only be set up and used in conjunction with this .
