Outputs - Siemens Simatic Manual

Fail-safe function blocks for storage and retrieval machines
3.6.2.2

Outputs

Name
SLS_THRESHOLD
SLS_OK
X_NEGATIVE_OK
X_POSITIVE_OK
MOVE_NEGATIVE_OK
MOVE_POSITIVE_OK
ACK_REQ
ERROR
DIAG
3.6.2.3 Structure of DIAG
Bit
Description
No.
0 Lower end position was fallen below
1 Upper end position was exceeded
2 Retraction velocity exceeded
3 Parameterizing error envelope curve,
for residual distance 0, the velocity is
not 0
S7-Distributed Safety/SIMATIC Safety - fail-safe function blocks for storage and retrieval machines
Data type Description
Int SLS limit [SLU/min]
The maximum permissible traversing velocity effective at
this time is output at this output. This is cyclically calculat-
ed in the block using the parameterized ramp function.
Bool Status, SLS limit
1: SAFE_V is less than/equal to SLS_THRESHOLD
0: SAFE_V has exceeded the SLS_THRESHOLD value.
A stop response should be initiated if this output changes
to 0.
Bool Status, minimum position
1: SAFE_POS is greater than/equal to X_NEGATIVE
0: SAFE_POS has fallen below the value of X_NEGATIVE.
A stop response should be initiated if this output changes
to 0.
Bool Status, maximum position
1: SAFE_POS is less than/equal to X_POSITIVE
0: SAFE_POS has exceeded the value of X_POSITIVE.
A stop response should be initiated if this output changes
to 0.
Bool Motion permitted in the negative direction
If a 0 signal is available at this output, then it is not permis-
sible that the machine continues to travel in the negative
direction. The output is then set to 0, as soon as
SAFE_POS assumes values less than X_NEGATIVE.
If SAFE_POS again lies above X_NEGATIVE, then after
acknowledgment, the output is set again.
Bool Motion permitted in the positive direction
If a 0 signal is available at this output, then it is not permis-
sible that the machine continues to travel in the positive
direction. The output is then set to 0, as soon as
SAFE_POS assumes values greater than X_POSITIVE.
If SAFE_POS again lies below X_POSITIVE, then after
acknowledgment, the output is set again.
Bool Acknowledgment request
If a fault has occurred, but is no longer active, and can
therefore be acknowledged, then this block indicates this
using a 1 signal at ACK_REQ.
Bool Error
This output is set if the block has been incorrectly parame-
terized – or if the block identifies a potentially dangerous
combination of input signals in operation. The output re-
mains set until an error is no longer active and has been
acknowledged.
Diagnostic word
Word
Information regarding the function status and errors of the
block are output here.
Reset condition
While retracting, SAFE_POS >= X_NEGATIVE
and positive edge at ACK
While retracting, SAFE_POS <= X_POSITIVE and
positive edge at ACK
SAFE_V <= SLS_THRESHOLD and positive edge
at ACK
Envelope curve parameterized to according to
3.6.3
- 3-33 -