Siemens SIMATIC S7-400H - System States of the S7-400 H; The System States of the S7-400 H; Table 11- 1 Overview of S7-400 H System States

System and operating states of the S7–400H
11.2 System states of the S7–400H
S7-400H
124 System Manual, 03/2012, A5E00267695-11
11.2 System states of the S7–400H
11.2.1 The system states of the S7-400H
The system states of the S7-400H result from the operating states of the two CPUs. The
term "system state" is used as a simplified term which identifies the concurrent operating
states of the two CPUs.
Example: Instead of "the master CPU is in RUN and the reserve CPU is in LINK-UP mode"
we say "the S7-400H system is in link-up mode".
Overview of system states
The table below provides an overview of the possible states of the S7-400H system.
Table 11- 1 Overview of S7-400H system states
System states of the S7–400H Operating states of the two CPUs
Master Reserve
Stop STOP STOP, power off, DEFECTIVE
Start-up STARTUP STOP, power off, DEFECTIVE, no
synchronization
Single mode RUN STOP, ERROR-SEARCH, power off,
DEFECTIVE, no synchronization
Link-up RUN STARTUP, LINK-UP
Update RUN UPDATE
Redundant RUN RUN
Hold HOLD STOP, ERROR-SEARCH, power off,
DEFECTIVE, no synchronization