HEIDENHAIN TNC 640 User Manual page 144

4
Machine coordinate system M-CS
The machine coordinate system corresponds to the description of
kinematics and therefore to the actual mechanical design of the
machine tool.
Because the mechanics of a machine tool never precisely
correspond to a Cartesian coordinate system, the machine
coordinate system consists of several one-dimensional coordinate
systems. These one-dimensional coordinate systems correspond to
the physical machine axes that are not obligatorily perpendicular to
each other.
The position and orientation of the one-dimensional coordinate
systems are defined with the aid of translations and rotations
based on the spindle tip in the description of kinematics.
The position of the coordinate origin, the so-called machine
datum, is defined by the machine manufacturer during machine
configuration. The values in the machine configuration define the
zero positions of the encoders and the corresponding machine
axes. The machine datum does not necessarily have to be located
in the theoretical intersection of the physical axes. It can therefore
also be located outside of the traverse range.
Because the machine configuration values cannot be modified by
the user, the machine coordinate system is used for determining
constant positions, e.g. the tool change point.
Soft key Application
The user can define shifts in the machine coordi-
nate system according to the specific axis with use
of the OFFSET values of the preset table.
The machine tool builder configures the OFFSET
columns of the preset management in accordance with
the machine.
Further information:
Danger of collision!
Your control may feature an additional pallet preset table,
depending on the machine. In this table the machine tool builder
can define OFFSET values that take effect before the OFFSET
values you specify in the preset table become effective. The PAL
tab of the expanded status display indicates whether a pallet
preset is active, and which one. Since the OFFSET values of the
pallet preset table are neither visible nor editable, there is a risk
of collision during any movement!
Refer to the machine tool builder's documentation
Use pallet presets only in conjunction with pallets
Check the display of the PAL tab before you start machining
144
"Managing presets", page 689
NOTICE
Fundamentals, File Management | Fundamentals
HEIDENHAIN | TNC 640 | ISO Programming User's Manual | 10/2017
MZP
Machine datum (MZP)