Siemens SINUMERIK 840C Operator's Manual page 291

12 Abbreviations / Glossary
Directory path
DRAM
DRF
Drift compensation
EDIT key
Editor
EMC
Enter box
EPROM
Feed override
Feedforward
control
File
File type
Flash EPROM
Helical
interpolation
12-6
This specifies the position of a file in the directory hierarchy.
(Dynamic Random Access Memory): Volatile memory chip with direct access
to each individual memory location. The locations retain their contents as long
as they are supplied with electrical power.
Differential Resolver Function: NC function that generates an incremental zero
offset in the Automatic mode with an electronic handwheel.
SINUMERIK 840C has a semi-automatic drift compensation function which
compensates the drift of the drive due to temperature changes. Drift
compensation is needed in order to eliminate the permanent contour offset
which results from the accumulative following error.
Key on the operator panel:
In NCK areas: Edit existing values
In MMC areas: Same function as tabulator key on the MF2 keyboard
The editor allows texts/program blocks to be edited, added to, pushed together,
and inserted.
Electromagnetic compatibility is understood to mean the capability of an item
of electrical equipment to function without fault in a given environment
without having an unacceptable influence on the surroundings.
Predefined area for entering values and texts.
(Erasable Programmable Read Only Memory): Non-volatile programmable
memory which retains its contents even if the power is switched off.
The programmed feedrate is modified from the machine control panel or from
the PLC (0 - 120%).
By means of the feedforward control, the velocity setpoints calculated by the
interpolator are output directly to the drive, i.e. without looping through the
position control. Inaccuracies in the contour, caused by the following error,
can be almost entirely eliminated by the dynamic, acceleration-dependent
feedforward control. This results in good machining accuracy even at high
contouring velocities.
Collection of data and/or text
Possible types of files, e.g. part programs, zero offsets, R parameters, etc.
Non-volatile programmable memory with high memory density that retains its
contents even if the power is switched off.
Helical interpolation is a great help in producing internal or external threads
with form cutters and for milling lubrication groups. The helical path is made
up of two motions:
•
Circular motion in a plane
•
Linear motion perpendicular to this plane.
6FC5198-6AA60-0BP1 © Siemens AG 1999 All Rights Reserved
SINUMERIK 840C, OEM Version for Windows (BA)
01.99