Siemens SINUMERIK 840D Description Of Functions page 149

11.03
3.10 Safe programable logic (SPL) (840D SW 4.4.18)
The following circuit applies:
Three disable inputs E1 to E3
Two acknowledgement inputs Q1
and Q2
Three timer initialization values
TI1 to TI3
One timer value TM1
Four output values A0 to A3
Initialization in the part On initialization, the connection is defined for the function block. The input-
output variables of the function block are assigned to the required system
program
variables ($A_MARKERSI, $A_INSE, $A_OUTSE,...). The following functions
must be called:
SIRELIN: This language command assigns the input variables Q1, Q2, E1, E2
and E3 to the safety relay x (x = 1..4). The return value contains the number of
the first incorrect parameter; the value 0 indicates that the parameter
assignment is correct.
Syntax:
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SINUMERIK 840D/SIMODRIVE 611 digital SINUMERIK Safety Integrated (FBSI) - Edition 11.03
If one of these inputs is set to 0, the direct output
A0 is set to 0. Outputs A1 to A3 switch with the
delay of timer 1.3. If one of these inputs is not
used, then it is internally set to "1" as static signal.
One of these inputs must also be used to initiate
the test operation for the safety relay (forced
checking procedure).
Q1 must be supplied with the signal from the real
acknowledgement.
Q2 is only used to automatically acknowledge the
safe software relay as part of the forced checking
procedure. The software relay itself does not have
to be subject to a forced checking procedure.
However, if the Emergency Stop function is
executed and if external actuators must be
subject to a forced checking procedure, then if the
relay drops-out during the Emergency Stop test
then it can be acknowledged using Q2 (in a
defined time window, refer to TM1).
Also this input must be connected with a safety
system variable (also if the signal is not used) –
preferably with a $A_MARKERSI – in order to
detect that this acknowledge signal is available as
steady-state signal in the crosswise data
comparison with the PLC. The associated
comparison data in the PLC must have a steady-
state 0 signal level (error detection using different
states of the particular SPL marker for the PLC
and NCK.
The times after which outputs A1 to A3 are
switched to 0 given a negative edge in output
signal A0 are defined here.
This limit value is used to define the maximum
time that the shutdown inputs E1 to E3 (and their
AND logic operation) may have been to a 0 signal
level so that they can still be acknowledged using
Q2. This therefore guarantees that Q2 can only
be effective as automatic acknowledgement for
the forced checking procedure within a defined
time window after the relay has dropped-out
(been de-energized). It is not permissible that Q2
is used to acknowledge a "real" shutdown.
A0 supplies the result of ANDing E1 to E3 without
delay. Outputs A1 to A3 supply the same result
for positive edges of A0; for negative edges, the
results are delayed by the timer initialization TI1 to
TI3.
A0 to A3 do not produce a result after startup until
an acknowledgement has been received via Q1.
SIRELIN(x,status,"Q1","Q2","E1","E2","E3")
3 Safety-Related Functions
3-149