Siemens SIMATIC S7-400H System Manual page 7

11 System and operating states of the S7-400H ........................................................................................ 121
11.1 Introduction ................................................................................................................................121
11.2 System states of the S7-400H...................................................................................................124
11.2.1 The system states of the S7-400H ............................................................................................124
11.2.2 Displaying and changing the system state of a fault-tolerant system........................................125
11.2.3 System status change from the STOP system state .................................................................126
11.2.4 System status change from the standalone mode system status .............................................126
11.2.5 System status change from the redundant system state...........................................................127
11.2.6 System diagnostics of a fault-tolerant system ...........................................................................128
11.3 The operating states of the CPUs..............................................................................................130
11.3.1 STOP mode ...............................................................................................................................131
11.3.2 STARTUP mode ........................................................................................................................132
11.3.3 LINK-UP and UPDATE modes ..................................................................................................133
11.3.4 RUN mode .................................................................................................................................133
11.3.5 HOLD mode ...............................................................................................................................135
11.3.6 ERROR-SEARCH mode............................................................................................................135
11.4 Self-test ......................................................................................................................................137
11.5 Evaluation of hardware interrupts in the S7-400H system ........................................................140
12 Link-up and update ................................................................................................................................ 141
12.1 Effects of link-up and updating...................................................................................................141
12.2 Conditions for link-up and update ..............................................................................................142
12.3 Link-up and update sequence....................................................................................................143
12.3.1 Link-up sequence.......................................................................................................................147
12.3.2 Update sequence.......................................................................................................................149
12.3.3 Switch to CPU with modified configuration or expanded memory configuration .......................152
12.3.4 Disabling of link-up and update..................................................................................................154
12.4 Time monitoring .........................................................................................................................155
12.4.1 Time response ...........................................................................................................................158
12.4.2 Determining the monitoring times ..............................................................................................159
12.4.3 Performance values for link-up and update ...............................................................................166
12.4.4 Influences on time response ......................................................................................................167
12.5 Special features in link-up and update operations.....................................................................168
13 Using I/Os in S7-400H .......................................................................................................................... 169
13.1 Introduction ................................................................................................................................169
13.2 Using single-channel, one-sided I/Os ........................................................................................171
13.3 Using single-channel switched I/O.............................................................................................173
13.4 Connecting redundant I/O to the PROFIBUS DP interface .......................................................177
13.4.1 Signal modules for redundancy .................................................................................................187
13.4.2 Evaluating the passivation status ..............................................................................................206
13.5 Other options for connecting redundant I/Os.............................................................................207
S7-400H
System Manual, 03/2012, A5E00267695-11
Table of contents
7