Glossary - Siemens SINUMERIK 840D sl Programming Manual

Glossary

Actual/set difference
Difference between measured and expected value.
Asynchronous subroutine
Part program that can be started asynchronously to (independently of) the current program
status using an interrupt signal (e.g. "Rapid NC input" signal).
Calibration
When calibrating, the trigger points of the probe are identified and saved in the cycle setting
data from SD 54600.
Calibration tool
Is a special tool (usually a cylindrical stylus), whose dimensions are known and that is used
for precisely determining the distances between the machine zero and the probe trigger point
(of the workpiece probe).
Collision monitoring
In the context of measuring cycles, this is a function that monitors all intermediate positions
generated within the measuring cycle for the switching signal of the probe. When the probe
switches, motion is stopped immediately and an alarm message is output.
Delete distance-to-go
If a measuring point is to be approached, a traverse command is transmitted to the position
control loop and the probe is moved towards the measuring point. A point behind the expected
measuring point is defined as setpoint position. As soon as the probe makes contact, the actual
axis value at the time the switching position is reached is measured and the drive is stopped.
The remaining "distance-to-go" is deleted.
Differential measurement
Differential measurement means that the 1st measuring point is measured twice, once with a
180 degree spindle reversal (rotation of the probe), i.e. opposite the cycle start position and
once with the spindle position that was available at the start of the cycle. This procedure allows
uncalibrated probes to be used without imposing less stringent precision requirements!
Measuring cycles
Programming Manual, 12/2017, 6FC5398-4BP40-6BA1
359