Siemens SINUMERIK 828D Programming Manual page 595

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.
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.
Programming key
Character and character strings that have a defined meaning in the programming language
for → part programs.
Protection zone
Three-dimensional zone within the → working area into which the tool tip must not pass.
Quadrant error compensation
Contour errors at quadrant transitions, which arise as a result of changing friction conditions
on the guideways, can be virtually entirely eliminated with the quadrant error compensation.
Parameterization of the quadrant error compensation is performed by means of a circuit test.
R parameters
Arithmetic parameter that can be set or queried by the programmer of the → part program for
any purpose in the program.
Fundamentals
Programming Manual, 07/2010, 6FC5398-1BP40-0BA0
Glossary
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