Siemens CPU 410-5H Process Automation System Manual page 156

System modifications during redundant operation
10.5 Editing CPU parameters
Tab
Watchdog interrupt (for each watchdog
interrupt OB)
Diagnostics/clock
Security
H parameter
Modifying these parameters also modifies the memory content.
*)
The selected new values should match both the currently loaded and the planned new user
program.
Starting situation
The fault-tolerant system is operating in redundant system mode.
Procedure
To edit the CPU parameters of a fault-tolerant system, follow the steps outlined below.
Details of each step are described in a subsection.
Step What to do?
1 Editing CPU parameters offline
2 Stopping the reserve CPU
3 Downloading modified CPU parameters to the reserve
CPU
4 Switching to a CPU with modified configuration
5 Transition to redundant system mode
156
Editable parameter
Starting date
Time
Execution
Phase offset
Correction factor
Security level and password
Test cycle time
Maximum cycle time extension
Maximum communication delay
Maximum inhibit time for priority classes > 15
Minimum I/O retention time
See section
Step 1: Editing CPU parameters offline
(Page 157)
Step 2: Stopping the reserve CPU (Page 157)
Step 3: Downloading a new hardware
configuration to the reserve CPU (Page 158)
Step 4: Switching to CPU with modified
configuration (Page 158)
Step 5: Transition to redundant system mode
(Page 159)
CPU 410-5H Process Automation/CPU 410 SMART
System Manual, 10/2013, A5E32631667-AA