Siemens SINUMERIK 840D sl Programming Manual page 931

PLC
Programmable Logic Control: → Programmable logic controller. Component of → NC:
Programmable controller for processing the control logic of the machine tool.
PLC program memory
SINUMERIK 840D: The PLC user program, the user data and the basic PLC program are
stored together in the PLC user memory.
PLC pogramming
The PLC is programmed using the STEP 7 software. The STEP 7 programming software is
based on the WINDOWS standard operating system and contains the STEP 5 programming
functions with innovative enhancements.
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.
Job Planning
Programming Manual, 06/2009, 6FC5398-2BP20-0BA0
Glossary
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