Siemens sinumerik 840D sl Function Manual page 524

• Control options via the PLC interface
• Status data of clearance control
• Sensor signal
2.4 Sensor collision monitoring
Sensor signal
If the clearance sensor used has an additional "sensor collision" signal for detecting a
collision between the sensor and the workpiece being machined, this signal can be made
available to the clearance control function via a digital NCK peripheral input.
In response to this signal, the clearance control function applies a retraction motion in all
clearance-controlled axes. The retraction motion is executed independently of the current
value of the velocity override with maximum traversing velocity in a positive control direction
until the currently valid upper limit of the control range is reached. Path motion is stopped
simultaneously.
Once all traversing movements have come to a standstill, part program processing can be
resumed with NC START.
Parameterization
The digital peripheral input, which the "sensor collision" signal is wired to, is assigned to the
clearance control function via the following machine data:
MD62504 $MC_CLC_SENSOR_TOUCHED_INPUT (digital peripheral input for "sensor
collision" signal)
The digital peripheral input is specified by entering the input number in the same way as
$A_IN/$A_OUT digital I/O peripheral system variables are specified ($A_IN[
If a negative input number is entered, the "sensor collision" signal will be processed with
internal inversion by the clearance control function (fail safe method).
Special functions: Clearance Control (TE1)
Function Manual, 11/2006, 6FC5397-2BP10-2BA0
The following signals are available at the PLC interface:
Status signals:
– Closed-loop control active
– Overlaying movement at standstill
– Lower limit reached
– Upper limit reached.
Control signals:
– Path override for sensor movement active
Both the current values and the min/max values of the sensor signal and of the position
offset are available as GUD and/or OPI variables.
The sensor signal can be smoothed via a PT1 filter with adjustable time constant.
Detailed description
2.4 Sensor collision monitoring
input number
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