Siemens SINUMERIK 840DE Programming Manual page 489

Messages
All messages programmed in the parts program and -> alarms recognized by the system are
output on the operator panel in plain text with the date and time and a symbol indicating the
cancel criterion. The display is divided into alarms and messages.
Metric measuring system
Standardized system of units: for lengths in millimeters (mm), meters (m), etc.
Mirroring
Mirroring inverts the signs of the coordinate values of a contour with respect to an axis. It is
possible to mirror in relation to more than one axis at a time.
Mode group
At any one time, all axes/spindles are assigned to a specific channel. Each channel is
assigned to a mode group. The same -> mode is always assigned to the channels in a mode
group.
Mounting rail
A mounting rail is used to attach the modules of an S7-300.
Multipoint interface
The multipoint interface (MPI) is a 9-pole Sub-D interface. A configurable number of devices
can be connected to a multipoint interface and then communicate with each other.
• Programming devices
• Operator control and monitoring equipment
• Further automation systems
The parameter block "Multipoint Interface MPI" of the CPU contains the -> parameters,
which define the properties of the multipoint interface.
Names
The words according to DIN 66025 are supplemented by the identifiers (names) for variables
(computer variable, system variable, user variable), for subroutines, for vocabulary words
and words with several address letters. In terms of the block structure, these supplements
have the same significance as the words. Identifiers must be unique. The same identifier
must not be used for different objects.
NC
Numerical Control: NC control incorporates all the components of the of the machine tool
control system: -> NCK, -> PLC, MMC/HMI, -> COM.
Fundamentals
Programming Manual, 10.2004 Edition, 6FC5 298-7AB00-0BP1
Glossary
Glossary-13