Siemens Sinumerik 840D sl Function Manual page 401

10/15
36942
MD number
Default value: 0.1
Change becomes effective after: POWER ON
Data type: DOUBLE
Meaning:
Special cases, errors,...
36944
MD number
Default value: 0.01
Change becomes effective after: POWER ON
Data type: DOUBLE
Meaning:
Special cases, errors,...
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SINUMERIK 840D sl/SINAMICS S120 SINUMERIK Safety Integrated (FBSI sl) - - 10.2015 Edition
$MA_SAFE_POS_TOL
Tolerance, actual value comparison (crosswise)
Min. input limit: 0.001
Protection level: 7/2
Due to the fact that encoders are not mounted at identical locations and the effect of back-
lash, torsion, leadscrew errors etc. the actual positions sensed simultaneously by the NCK
and drive may differ from one another.
The tolerance bandwidth for the crosswise comparison of the actual positions in the two
monitoring channels is specified in this machine data.
When defining this tolerance value, primarily the values from the machine- -specific risk
analysis must be taken into account.
Stop response STOP F is activated when the tolerance bandwidth is violated.
$MA_SAFE_REFP_POS_TOL
Tolerance, actual value comparison (referencing)
Min. input limit: 0.0
Protection level: 7/2
This machine data specifies the tolerance for checking the actual values after referencing
(for incremental encoders) or when powering- -up (for absolute encoders).
An absolute actual axis position is determined by referencing. A second absolute actual
position is calculated from the last stop position that was saved prior to the control being
powered- -down and the distance traversed since power- -on. The control system checks the
actual values after referencing on the basis of these two absolute positions, the traversed
distance and this machine data.
The following factors must be taken into consideration when calculating tolerance values:
Backlash, leadscrew errors, compensation factors (max. compensation values for SSFK,
sag and temperature compensation), temperature errors, torsion (2- -encoder system), gear-
box tolerance for selector gearboxes, coarser resolution (2- -encoder system), oscillating
distance/range for selector gearboxes.
Note:
If the two absolute actual positions deviate from one another by more than the value set in
this data - - with a valid user agreement - - then Alarm 27001 is output with Fault code 1003
and a new user agreement is required for referencing.
8.1 Machine data for SINUMERIK 840D sl
Max. input limit: 360.
Max. input limit: 36.
Data Description
Unit: mm, inches,
degrees
Unit: mm, inches,
degrees
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