Siemens SINUMERIK 840D sl Function Manual page 71

<SysVar_Out>:
<SysVar_In>:
Programming:
Program code
N100 FCTDEF(2, 0, 120, 160, -2)
N110 ID=1 DO SYNFCT(2, $AC_OVR[X], $AA_LOAD[X])
Example: Clearance control
Figure 3-5
The clearance control of the infeed axis Z is performed via the FCTDEF and SYNFCT functions
as well as by the system variables $AA_OFF and $A_INA.
Supplementary conditions:
● The analog voltage of the clearance sensor is connected via the analog input $A_INA[3].
● The position deviations are summated in $AA_OFF (integrated):
MD36750 $MA_AA_OFF_MODE, bit 0 = 1
● If the upper limit of the Z axis is exceeded by 1 mm, the X axis is stopped:
SD43350 $SA_AA_OFF_LIMIT[Z] = 1
See also Chapter "Overlaid movements ($AA_OFF) (Page 45)."
Note
$AA_OFF is effective in the basic coordinate system (BCS)
The offset is effective before the kinematic transformation in the basic coordinate system
(BCS). The example therefore cannot be used for a clearance control in the orientation
direction of the tool (workpiece coordinate system WCS).
For clearance control system with high dynamic response or 3D clearance control, see:
References:
Function Manual Special Functions; Clearance Control (TE1)
Customized responses
When the limit value SD43350 $SA_AA_OFF_LIMIT is reached, customized responses can
be triggered, for example:
● Chapter "Override ($A...OVR) (Page 36)"
● Chapter "User-specific error reactions (SETAL) (Page 115)"
Synchronized actions
Function Manual, 08/2018, 6FC5397-5BP40-6BA2
$AC_OVR (path override can be specified via synchronized action)
$AA_LOAD (drive load)
Clearance control: Principle
Detailed description
3.7 Actions in synchronized actions
71