Siemens SINUMERIK 840DE Programming Manual page 493

Position 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 with -> path axes.
Power on
Switching the control off and back on again.
Preset
The preset function can be used to redefine the control zero in the machine coordinate
system. Preset does not move the axes, but a new position value is entered for the current
axis positions.
Program
1. Control operating area
2. Sequence of instructions to the control
Program block
Program blocks contain the main and subprograms of the -> parts programs.
Programmable frames
Programmable -> frames can be used to define new coordinate system starting points
dynamically while the parts program is running. A distinction is made between absolute
definition using a new frame and additive definition with reference to an existing starting
point.
Programmable Logic Controller
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
Characters and character sequences, which have a defined meaning in the programming
language for -> parts programs (see Programming Guide).
Fundamentals
Programming Manual, 10.2004 Edition, 6FC5 298-7AB00-0BP1
Glossary
Glossary-17