Logic Gating Functions: Source And Reaction Linking - Siemens SINUMERIK 840D sl Function Manual

General trigger sources
• Digital inputs (NCU module or terminal block) or the internal control image of digital
outputs that can be read back: $A_IN, $A_OUT
• Channel status: $AC_STAT
• VDI signals
• System variables written from the PLC: $A_DBB, $A_DBW, $A_DBD
It is not recommended to use these system variables, written by the PLC for time-critical
signals, as in this case, the PLC cycle time is included in the total response time.
Nevertheless, it is an appropriate way for the PLC to influence the sequence or release of
the extended stop and retract function. However, linking-in PLC states in such a fashion
does make sense if these are exclusively input from the PLC (e.g. Emergency-Stop, reset
button, stop button)
• Group signals from alarms: $AC_ALARM_STAT
Axial trigger sources
• Emergency retraction threshold of the following axis (synchronism difference of the
electronic coupling: $VA_EG_SYNCDIFF[following axis]
Alarm responses
When ESR is active, the alarm responses NOREADY and STOPBYALARM are delayed by
one IPO cycle. The following self-clearing alarm is displayed to indicate this delay: Alarm
21600 "Monitoring for ESR active".
Note
The display of this alarm can be suppressed by:
MD11410 $MN_SUPPRESS_ALARM_MASK, bit 16 = 1
6.2.7

Logic gating functions: Source and reaction linking

The flexible logic operation possibilities of the static synchronized actions can be used to
trigger specific reactions based on sources. Linking all relevant sources using static
synchronized actions is the responsibility of the user/machine manufacturer. They can
selectively evaluate the source system variables as a whole or by means of bit masks, and
then make a logic operation with their desired reactions. The static synchronous actions are
effective in all operating modes. A detailed description of how to use synchronous actions can
be found in:
References:
• Function Manual, Synchronized Actions
• Programming Manual Work Preparation (Synchronized Actions, System Variables)
Linking of axial sources with global or channel specific sources can be configured variably
with the aid of $AA_TYP (axis type).
Special Functions
Function Manual, 09/2011, 6FC5397-2BP40-2BA0
R3: Extended stop and retract
6.2 Control-managed ESR
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