35.9 State Transition Of A System Using The Sil2 Process Cpu - Mitsubishi Electric MELSEC iQ-R-R00CPU User Manual

35.9
State Transition of a System Using the SIL2
Process CPU
The following figure shows the state transition of the system after start-up.
System B is powered on.
(Forced start of the control system)
Backup mode
System A: Off
System B: Control system
System A is powered off.
*1 When both systems are powered off, both systems enter the power-off state regardless of the system type.
35 BASIC CONCEPT
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35.9 State Transition of a System Using the SIL2 Process CPU

Both systems are powered off.
System A: Off
System B: Off
System A is powered off.
System A: Control system
(Systems are switched.)
System B: Standby system
System A is powered on.
System A: Standby system
System B: Control system
*1
System A is powered on.
(Forced start of the control system)
Both systems are
powered on.
System B is powered off.
System B is powered on.
System switching
System A: Control system
System B: Off
System B is powered off.
(Systems are switched.)