Siemens SIMATIC PCS 7 System Manual page 7

16.6.4 S7 communication ................................................................................................................ 241
16.6.5 S7 routing .............................................................................................................................. 242
16.6.6 Data set routing ..................................................................................................................... 246
16.6.7 SNMP network protocol ........................................................................................................ 247
16.6.8 Open Communication Via Industrial Ethernet ...................................................................... 248
16.7 Basics and terminology of fault-tolerant communication ...................................................... 251
16.8 Usable networks ................................................................................................................... 255
16.9 Communication via S7 connections ...................................................................................... 256
16.9.1 Communication via S7 connections - one-sided mode ........................................................ 257
16.9.2 Communication via redundant S7 connections .................................................................... 259
16.9.3 Communication via point-to-point CP on the ET 200M ........................................................ 260
16.9.4 Custom connection to single-channel systems .................................................................... 262
16.10 Communication via fault-tolerant S7 connections ................................................................ 263
16.10.1 Communication between fault-tolerant systems ................................................................... 265
16.10.2 Communication between fault-tolerant systems and a fault-tolerant CPU ........................... 268
16.10.3 Communication between fault-tolerant systems and PCs .................................................... 269
16.11 Consistent data ..................................................................................................................... 271
16.11.1 Consistency of communication blocks and functions ........................................................... 271
16.11.2 Consistency rules for SFB 14 "GET" or read variable, and SFB 15 "PUT" or write
variable ................................................................................................................................. 271
16.11.3 Consistent reading and writing of data from and to DP standard slaves/IO devices ........... 272
16.12 Link-up and update sequence .............................................................................................. 274
16.12.1 Link-up sequence .................................................................................................................. 277
16.12.2 Update sequence .................................................................................................................. 278
16.12.3 Switch to CPU with modified configuration ........................................................................... 281
16.12.4 Disabling of link-up and update ............................................................................................ 282
16.13 The user program ................................................................................................................. 283
16.14 Other options for connecting redundant I/Os ........................................................................ 284
16.15 Cycle and response times of the CPU 410-5H ..................................................................... 287
16.15.1 Cycle time ............................................................................................................................. 287
16.15.2 Calculating the cycle time ..................................................................................................... 289
16.15.3 Cycle load due to communication ......................................................................................... 293
16.15.4 Response time ...................................................................................................................... 295
16.15.5 Calculating cycle and response times .................................................................................. 300
16.15.6 Examples of calculating the cycle and response times ........................................................ 301
16.15.7 Interrupt response time ......................................................................................................... 304
16.15.8 Example of calculation of the interrupt response time .......................................................... 306
16.15.9 Reproducibility of delay and watchdog interrupts ................................................................. 307
16.16 Runtimes of the FCs and FBs for redundant I/Os ................................................................ 308
A Characteristic values of redundant automation systems ...................................................................... 311
A.1 Basic concepts ...................................................................................................................... 311
A.2 Comparison of MTBF for selected configurations ................................................................ 315
A.2.1 System configurations with redundant CPU 410-5H ............................................................ 315
A.2.2 System configurations with distributed I/Os .......................................................................... 316
A.2.3 Comparison of system configurations with standard and fault-tolerant communication ...... 320
CPU 410-5H Process Automation/CPU 410 SMART
System Manual, 09/2014, A5E32631667-AB
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