Siemens SINUMERIK 840D sl Function Manual page 777

Polar coordinates
A coordinate system, which defines the position of a point on a plane in terms of its distance
from the origin and the angle formed by the radius vector with a defined axis.
Polynomial interpolation
Polynomial interpolation enables a wide variety of curve characteristics to be generated, such
as straight line, parabolic, exponential functions (SINUMERIK 840D).
Positioning axis
Axis that performs an auxiliary movement on a machine tool (e.g. tool magazine, pallet
transport). Positioning axes are axes that do not interpolate with → path axes.
Pre-coincidence
Block change occurs already when the path distance approaches an amount equal to a
specifiable delta of the end position.
Program block
Program blocks contain the main program and subroutines of → part programs.
Program level
A part program started in the channel runs as a → main program on program level 0 (main
program level). Any part program called up in the main program runs as a → subprogram on
a program level 1 ... n of its own.
Programmable frames
Programmable → frames enable dynamic definition of new coordinate system output points
while the part program is being executed. A distinction is made between absolute definition
using a new frame and additive definition with reference to an existing starting point.
Programmable Logic Control
Programmable logic controllers (PLC) are electronic controls, the function of which is stored
as a program in the control unit. This means that the layout and wiring of the device do not
depend on the function of the control. The programmable logic controller has the same
structure as a computer; it consists of a CPU (central module) with memory, input/output
modules and an internal bus system. The peripherals and the programming language are
matched to the requirements of the control technology.
Programmable working area limitation
Limitation of the motion space of the tool to a space defined by programmed limitations.
Special Functions
Function Manual, 09/2011, 6FC5397-2BP40-2BA0
Glossary
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