Siemens SINUMERIK 840D sl Function Manual page 1100

Glossary
Peripheral module
I/O modules represent the link between the CPU and the process.
I/O modules are:
● → Digital input/output modules
● → Analog input/output modules
● → Simulator modules
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 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, 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.
Position-time cams
The term "position-time cam" refers to a pair of software cams that can supply a pulse of a
certain duration at a defined axis position.
Pre-coincidence
Block change occurs already when the path distance approaches an amount equal to a
specifiable delta of the end position.
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Function Manual, 01/2008, 6FC5397-1BP10-3BA0
Extended Functions