HEIDENHAIN TNC 620 (34056x-04) Cycle programming - Manual (Page 449)

Fundamentals 19.1
19
TNC 620 | User's Manual Cycle Programming | 5/2013
449
probingFeedCalc determines the calculation of the probing feed
rate:
probingFeedCalc = ConstantTolerance:
The measuring tolerance remains constant regardless of the tool
radius. With very large tools, however, the feed rate for probing
is reduced to zero. The smaller you set the maximum permissible
rotational speed (
maxPeriphSpeedMeas) and the permissible
tolerance (
measureTolerance1), the sooner you will encounter this
effect.
probingFeedCalc = VariableTolerance:
The measuring tolerance is adjusted relative to the size of the tool
radius. This ensures a sufficient feed rate for probing even with
large tool radii. The TNC adjusts the measuring tolerance according
to the following table:
Tool radius Measuring tolerance
Up to 30 mm measureTolerance1
30 to 60 mm 2 •
measureTolerance1
60 to 90 mm 3 •
measureTolerance1
90 to 120 mm 4 • measureTolerance1
probingFeedCalc = ConstantFeed:
The feed rate for probing remains constant; the error of
measurement, however, rises linearly with the increase in tool
radius:
Measuring tolerance = r •
measureTolerance1/ 5 mm, where
r: Active tool radius in mm
measureTolerance1: Maximum permissible error of
measurement