Siemens Sinumerik 840D sl Programming Manual page 201

Metric units system
Standardized system of length units in millimeters, meters, etc.
Mirroring
Mirroring changes the sign of the coordinate value of a contour with reference to an axis.
Mirroring can be executed simultaneously for several axes.
Mode group
All axes/spindles are assigned at a randomly specified time to a single channel. Each
channel is assigned to a mode group (BAG). The same -> mode is always assigned to the
channels in a mode group.
Motion synchronization
This function can be used to trigger actions that run simultaneously (synchronously) with the
machining. The starting point of the actions is defined by a condition (e.g. the status of a
PLC input, the time that has elapsed since the start of a block). The start of motion-
synchronized actions is not linked to block limits. Examples of typical
motion-synchronized actions are: Transfer of M- and H-(auxiliary) functions at the PLC or
distance-to-go delete for certain axes.
Multipoint interface
The multipoint interface (MPI) is a nine-pin Sub D socket contact. A parameterizable number
of devices that communicate with one another can be connected to the MPI:
Programming devices
HMI systems
Other automation systems
The properties of the Multipoint Interface are defined with -> parameters in the "Multipoint
Interface MPI" parameter set in the CPU.
NC
"Numerical Control" = numerical control system; contains all components of the control
system of the machine tool: -> NCK, -> PLC, -> HMI, -> COM.
NCK
Numerical Control Kernel: Component of the NC control system, which executes -> part
programs and essentially coordinates the movements at the machine tool.
Net, Network
A net or network is the connection of several S7-300 and other automation or HMI devices
such as programming devices via -> connecting cables. The interconnected devices
exchange data across the network.
ISO Milling
Programming Manual, 06/09, 6FC5398-7BP10-1BA0
Glossary
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