HEIDENHAIN TNC 620 User Manual page 521

Danger of collision!
For nonreferenced axes, the TNC adopts the most
recently saved axis values. These values generally
are not the exact actual axis positions!
As a result, for example, the tool might not move
exactly along the actual tool direction. If the tool
is still in contact with the workpiece, it can cause
stress or damage to the tool and workpiece. Stress
or damage to the workpiece or tool can also be
caused by uncontrolled coasting or braking of axes
after a power interruption. Move the axes carefully if
the tool is still in contact with the workpiece. Set the
feed rate override to the smallest values possible. If
you use the handwheel, use a small feed rate factor.
The traverse range monitoring is not available for
nonreferenced axes. Observe the axes while you
move them. Do not move to the limits of traverse.
TNC 620 | User's Manual
HEIDENHAIN Conversational Programming | 3/2014
Program run 16.5
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