Technical data

AUTOMATIC WARM
RESTART
If there is a power failure/POWER OFF during RESTART or RUN,
when the power returns again/POWER ON, the CPU performs an
initialization routine and then attempts to perform a WARM
RESTART automatically, as long as DX 0 is correctly parameterized
(see Chapter 7).
Conditions: •• The selectors on all the CPUs and on the
coordinator remain set to RUN.
•• No errors are detected during the initialization.
• The CPU was not in STOP before the power
failure/POWER OFF.
If there is a power failure in an expansion unit (PEU signal), the CPU
changes to STOP. It remains in this state until the PEU signal is
cleared and then attempts to perform an AUTOMATIC WARM
RESTART or AUTOMATIC COLD RESTART.
RETENTIVE COLD
RESTART (from Version
-3UB12)
If the parameter "Retentive cold restart" is stored in DX 0, the system
program executes RETENTIVE COLD RESTART instead of WARM
RESTART. See the following section to find out how this differs to a
"normal" COLD RESTART.
RESTART Mode
CPU 928B Programming Guide
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