Siemens SINUMERIK 880 GA2, Руководство по планированию

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05.91 5 Description of Basic Signals (FY 0 ... FY 24)
5.1 PLC auxiliary signals
Example: Time alarm with Power Off
The PLC is operating in normal mode. A branch is made from OB 1 to a program block (in this
case represented by PB X).
Situation before warm restart:
A time alarm is present when program block PB X is called. The PLC operating system
therefore initially branches to OB 6. While OB 6 is being processed, the power supply to the
PLC fails. The processing levels of OB 1 and OB 6 are thus active at the time of the program
interrupt caused by the power failure.
Situation on warm restart:
The initial setting signals of all processing levels except OB 1 and OB 6 are set. Program
execution is resumed at the interruption point in OB 6. At the end of OB 6, OB 1 is
reactivated; that is to say the JU PB X command that was interrupted by the time alarm is first
concluded and routed to PB X. After the block end of OB 1 the PLC operating system sets the
initial setting signals for OB 1 and OB 6.
Setting initial setting signals on warm restart, example with interrupted time alarm
POWER OFF
a a a a a a a a a a a a a a a a a
a a a a a a a a a a a a a a a a a
a a a a a a a a a a a a a a a a a
a a a a a a a a a a a a a a a a a
OB 6
BE
a a a a a a a a a a a a a a a a a
a a a a a a a a a a a a a a a a a
a a a a a a a a a a a a a a a a a
a a a a a a a a a a a a a a a a a
OB 1
JU PB X
BE
a a a a a a a a a a a a a a a a a
a a a a a a a a a a a a a a a a a
a a a a a a a a a a a a a a a a a
a a a a a a a a a a a a a a a a a
PB X
BE
JU PB X is recovered
Time alarm
Warm restart with initial setting = 1
for all OBs except OB 1 and OB 6
a a a a a a a a a a a a a a a a a a a a a a a a a a a a a
a a a a a a a a a a a a a a a a a a a a a a a a a a a a a
a a a a a a a a a a a a a a a a a a a a a a a a a a a a a
a a a a a a a a a a a a a a a a a a a a a a a a a a a a a
a a a a a a a a a a a a a a a a a a a a a a a a a a a a a
a a a a a a a a a a a a a a a a a a a a a a a a a a a a a
a a a a a a a a a a a a a a a a a a a a a a a a a a a a a
Initial setting OB 1 = 1
Initial setting OB 6 = 1
The initial setting signals of the processing levels interrupted by Power Off (OB 1 and
OB 6 in this example) are not set until their remainder has been executed.
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5–3
SINUMERIK 880 (PJ)