Actual-Velocity Monitoring - Siemens SINUMERIK 840D sl Function Manual

A3: Axis Monitoring, Protection Zones
3.2 Axis monitoring functions
Speed-setpoint monitoring delay
To prevent an error reaction from occurring in every speed-limitation instance, a delay time
can be configured:
MD36220 $MA_CTRLOUT_LIMIT_TIME (speed-setpoint monitoring delay)
Only if the speed limitation is required for longer than the configured time does the
corresponding error reaction occur.
Effectiveness
The speed-setpoint monitoring is only active for closed-loop position-controlled axes and
cannot be deactivated.
Fault
If the configured delay time is exceeded, the following alarm appears:
25060 "Axis <Axis name> Speed-setpoint limitation"
The affected axis is stopped via the configured braking ramp in follow-up mode:
MD36610 $MA_AX_EMERGENCY_STOP_TIME
(maximum time for braking ramp when an error occurs)
Note
Upon reaching the speed-setpoint monitoring, the position feedback loop of the axis becomes
non-linear due to the limitation. Contour errors result if the axis is involved in generating the
contour.
3.2.4

Actual-velocity monitoring

Function
The actual-velocity monitoring checks that the actual velocity of a machine axis/spindle does
not exceed the configured threshold:
MD36200 $MA_AX_VELO_LIMIT (velocity-monitoring threshold)
The threshold should be 10-15% above the configured maximum velocity.
● For axes:
MD32000 $MA_MAX_AX_VELO (maximum axis velocity)
● For spindles:
MD35110 $MA_GEAR_STEP_MAX_VELO_LIMIT[n] (maximum speed of gear stage)
If you use this setting the speed will not normally exceed the velocity-monitoring threshold
(exception: Drive error).
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Function Manual, 01/2015, 6FC5397-0BP40-5BA2
Basic Functions