Outputs; Principle Of Operation; Parameterization - Siemens Simatic Manual

Fail-safe function blocks for storage and retrieval machines
OUT1_SCALE_DINT
OUT2_SCALE_DINT
3.3.2.2

Outputs

Name
OUT
SCALE_OK
3.3.3

Principle of operation

3.3.3.1

Parameterization

1. At input SCALE_Z the numerator is parameterized, at input SCALE_N the denominator of the
conversion factor from a 32-bit encoder raw value to 16 bit SLU.
2. If SCALE_N <= 0 is parameterized, then ERROR is set to 1, SCALE_OK is set to 0, and the
last valid value is output at OUT.
3. If the scale value is to be inverted, then this is realized using a negative sign of SCALE_Z.
4. LADDR_IO is used to define from which peripheral address of the standard block the 32-bit
value to be scaled is supplied.
5. Parameters MASK_OFFSET and MASK_LENGTH are used to define the screen form (mask)
for the position actual value in the encoder raw value.
6. If the sum of parameters MASK_OFFSET and MASK_LENGTH > 32, MASK_LENGTH < 16
or MASK_OFFSET < 0, then ERROR is set to 1 and SCALE_OK is set to zero, and the last
valid value is output at OUT.
7. The number of the instance DB of the block call should be parameterized at INSTANCE_ID.
8. If, at this input, a value is parameterize that differs from the actually used instance DB number,
then SCALE_OK changes to 0 – and the last valid value is output at OUT until SCALE_OK
again has a 1 signal.
9. Block SCALE_DINT in the standard program reads its parameterization from this instance DB.
10. Due to the fact that parameterization is realized using a block in the safety program – and not
directly at the standard program SCALE_DINT block, these parameters are taken into account
when generating the safety program signature.
11. Therefore, when the scaling factor is changed, this also influences the signature; further, the
scaling factor can only be modified when the safety program password is known.
12. The factor defined using SCALE_Z and SCALE_N depends on the resolution of the direct
measuring system, which is interconnected at LADDR_IO and the definition of unit SLU, as it
was defined at the input SLU_DEFINITION of the F_SAFE_POS block.
13. For a direct measuring system resolution of 1µm and a selected SLU_DEFINITION of 12mm
then a factor of 1:12000 would be obtained, for example; SCALE_Z would therefore be 1 and
SCALE_N correspondingly 12000.
Safety notes and instructions
It is not permissible that inputs SCALE_Z, SCALE_N, LADDR_IO and
INSTANCE_ID are interconnected with bit memories from the standard user pro-
gram. Only then is it guaranteed that the scaling parameterization cannot be
changed without knowing the safety program password.
S7-Distributed Safety/SIMATIC Safety - fail-safe function blocks for storage and retrieval machines
the SCALE_DINT block in the standard program.
Here, it is mandatory that precisely the same number as that
of the instance DB of the particular F_SCALE_DINT block is
parameterized.
OUT1 value of the "SCALE_DINT" block
This output should be connected with the corresponding out-
Word
put OUT1 of the SCALE_DINT block in the standard program
using a bit memory word.
OUT2 value of the "SCALE_DINT" block
This output should be connected with the corresponding out-
Word
put OUT2 of the SCALE_DINT block in the standard program
using a bit memory word.
Data type Description
Scaling result
Int
Scaling status
1: Scaling is valid if a currently scaled value is output at OUT
Bool 0: Error, the last valid value is output at OUT
A stop response should be initiated if this output changes to
0.
- 3-21 -