Siemens SINUMERIK 840D sl Programming Manual page 661

Path feed
Path feed acts on -> path axes. It represents the geometrical sum of the feeds on the
participating -> geometry axes.
Path velocity
The maximum programmable path velocity depends on the input resolution. For example,
with a resolution of 0.1 mm the maximum programmable path velocity is 1000 m/min.
PLC
Programmable Logic Control: Component of → NC: Programmable controller for processing
the control logic of the machine tool.
PLC program memory
SINUMERIK 840D: The PLC user program and the user data are stored together with the
PLC basic program in the PLC user memory.
PLC Programming
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 that defines the position of a point on a plane in terms of its distance
from the zero point and the angle formed by the radius vector with a defined axis.
Polynominal 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 which performs an auxiliary movement on a machine tool (e.g. tool magazine, pallet
transport). Positioning axes are axes that do not interpolate using → 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, 03/2006 Edition, 6FC5398-2BP10-1BA0
Glossary
Glossary-15