Monitoring Functions - Siemens SINUMERIK 840D Function Manual

17.14

Monitoring functions

Limitations
For manual traversing and manual traversing using a handwheel, the following limits apply:
● Working area limitation (the axis must be referenced).
● Software limit switches 1 and 2 (axis must be referenced)
● Hardware limit switches
The control ensures that the traversing movement is aborted as soon as the first valid limitation
has been reached. Velocity control ensures that deceleration is initiated early enough for the
axis to stop exactly at the limit position (e.g. software limit switch). Only when the hardware limit
switch is triggered does the axis stop abruptly with "rapid stop".
Alarms are triggered when the various limitations are reached (alarms 16016, 16017, 16020,
16021). The control automatically prevents further movement in this direction. The traversing
keys and the handwheel have no effect in this direction.
Note
The software limit switches and working-area limitations are only active if the axis has first been
referenced.
If a work offset (DRF offset) via handwheel is active for axes, the software limit switches for
these axes are monitored during the main run in JOG mode. This means that the jerk limitation
has no effect when the software limit switches are approached. After acceleration in
accordance with MD32300 $MA_MAX_AX_ACCEL (maximum axis acceleration) the velocity
is reduced at the software limit switch.
For further information on working area limitations and hardware and software limit switches,
see:
Further information
Function Manual Monitoring and Compensating; Axis monitoring, protection zones
Retract axis
The axis can be retracted from a limit position by moving it in the opposite direction.
Note
Machine manufacturer
The function for retracting an axis that has approached the limit position depends on the
machine manufacturer. Please refer to the machine manufacturer's documentation!
Maximum velocity and acceleration
The velocity and acceleration used when manually traversing are defined by the startup
engineer for specific axes using machine data. The control limits the values acting on the axes
to the maximum velocity and acceleration specifications.
Axes and spindles
Function Manual, 06/2019, A5E47437747B AA
H1: Manual traversing
17.14 Monitoring functions
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