Omron SYSMAC CS Series Operation Manual page 133

Description of Operation
1,2,3...
Loop Controller
Run
Function Block data
1. Read
RAM
Flash memory
■ Hot start
Use the hot start method when it is preferable to continue operations after a
short power interruption or it is necessary to use the same Remote/Local set-
ting, MV output value, and Auto/Manual setting that existed before the power
went OFF. A hot start cannot be performed if the backup capacitor has dis-
charged. (The backup capacitor can preserve the contents of RAM for about
24 hours for CS-series PLCs and 5 minutes for CJ-series PLCs.)
1. If the Function block data has been preserved by the backup capacitor, the
Board does not initialize the memory area used for operations or the MV
output, Auto/Manual switch, and Remote/Local switch settings.
2. The Board restarts operation with the settings that were preserved from
before the power interruption.
Loop Controller
Run
2. Preserve
RAM
1. Backup
Capacitor
Note The capacitor is backed up by the battery in the CPU Unit element
for CJ-series CPU Units.
Cold starts when a "hot started within specified time" is specified
A cold start will be used when a "hot started within specified time" is specified
but the power supply is interrupted longer than the specified time. The cold
start in this case, however, will differ from normal cold starts in that function
block data will not be read from the flash memory to RAM and HMI interface
send/receive data and receive data (SPs, PID parameters, etc.) for control
and operation blocks will not be read from the HMI interface data area (in the
EM Area in the CPU Unit). The function block data in RAM (backed up by a
capacitor (1)) will be used to initialize the MV, A/M switch, and R/L switch in
internal memory for processing (2) and then operation will be started.
Loop Controller
Run
RAM
Flash memory
Capacitor
(See note a.)
CPU Unit
Control and Operation Blocks'
send/receive and reception
data
Data area for
2. Read
the human-ma-
chine interface
(EM area)
CPU Unit
(See note.)
CPU Unit
(2) Initialize
Data area for
the human-ma-
chine interface
(EM area)
(1) Backup
Section 3-2
101