Glossary - Siemens Sinumerik 840D sl Programming Manual

Glossary

A spline
The Akima spline runs under a continuous through the programmed interpolation points (3rd
order polynomial) tangentially.
Absolute dimensions
A specification for the target of axis motion is defined by a dimension that refers to the origin
of the currently active coordinate system. See also -> incremental dimension.
AC (adaptive control)
A process variable (e.g. path- or axis-specific feedrate) can be controlled as a function of
another measured process variable (e.g. depending on spindle current). Typical application:
Maintenance of constant chip removal volume during grinding.
Acceleration and jerk limit
To achieve an optimal acceleration factor for the machine while preserving the mechanical
parts, the machining program offers the option of switching between instantaneous (inertia-
free) and constant (jerk-free) acceleration.
Access rights
The blocks of a CNC program are protected via the following 7-level system of
access-authorization restrictions:
● Three password levels, one each for the system manufacturer, the machine manufacturer
● Four key-operated switch settings, which can be evaluated via the PLC.
Activation / deactivation
Working area limitation is a means of limiting the axis motion over the restrictions set by the
limit switch. A pair of values can be specified for each axis with which the protection zone is
delimited.
Address
Addresses are fixed or variable identifiers for axes (X, Y, ...), spindle speed (S), feedrate (F),
circle radius (CR), etc.
ISO Milling
Programming Manual, 06/09, 6FC5398-7BP10-1BA0
and the user;
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