Siemens SINUMERIK 840D Description Of Functions page 247

11.03
If the difference between the position actual values is greater than the tolerance
window, the drive initiates an alarm (STOP F) and shuts down if at least one
monitoring function is active.
1344 $MD_SAFE_REFP_POS_TOL
Actual value tolerance safe axis position
Unit: Default:
µm or 10
mdegrees
Tolerance threshold for the actual value monitoring after referencing. A second
absolute actual position is calculated from the last standstill position that is
saved before the encoder is powered down and the distance traversed since
POWER ON. These two actual positions must be within the tolerance window
or else the axis cannot be referenced without a "user agreement". If the user
agreement is not present, alarm "axis not safely referenced" is output with error
code.
The following factors must be taken into consideration when calculating
tolerance values:
Backlash, leadscrew errors, temperature errors, torsion for 2-encoder systems,
gear play for selector gearboxes, lower resolution for 2-encoder systems,
oscillating travel for selector gearboxes.
1346 $MD_SAFE_VELO_X
Speed limit nx
Unit: Default:
mm/min, rpm 20
This data defines the speed limit n
Setting 0 means: n < n
1348 $MD_SAFE_STOP_VELO_TOL
Actual speed tolerance for SBR
Unit: Default:
mm/min, 300
inch/min, rpm
After activating the safe braking ramp (SBR), the actual speed plus the speed
tolerance, specified using this machine data, is activated as speed limit. If a
value > 0 is specified in this MD, a value, converted to the internal format, is
limited to >= 1.
Recommended settings: Refer to Chapter 3 "Safe braking ramp"
1349 $MD_SAFE__SLIP_VELO_TOL
Tolerance 2-encoder drift / slip
Unit: Default:
mm/min, 6
inch/min, rpm
The tolerance specified in this MD is used as the maximum permissible speed
difference between the NC and drive if the function in bit 3 of MD 1301 "Enable
actual value synchronization" is selected. The tolerance in this MD is then used
for the crosswise data comparison instead of the parameterized tolerance in
© Siemens AG 2003 All Rights Reserved
SINUMERIK 840D/SIMODRIVE 611 digital SINUMERIK Safety Integrated (FBSI) - Edition 11.03
4.2 Machine data for SIMODRIVE 611 digital
Minimum value: Maximum value:
0 36 000
Minimum value: Maximum value:
0 1 000
for SGA "n < n
x
is not active.
x
Minimum value: Maximum value:
0 20 000
Minimum value: Maximum value:
0 1000
4 Data Descriptions
611 digital
Relevant for:
FD/MSD
Data type: Becomes
long integer effective:
POWER ON
611 digital
Relevant for: Valid from:
FD/MSD SW4.2 for 840D
Data type: Becomes
float effective:
POWER ON
".
x
611 digital
Relevant for: Valid from:
FD/MSD SW4.2 for 840D
Data type: Becomes
float effective:
POWER ON
611 digital
Relevant for: Valid from:
FD/MSD SW5.2 for 840D
Data type: Becomes
float effective:
POWER ON
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