Siemens SINUMERIK 840D sl Function Manual page 959

CU
Transformation ratio
Curvature
The curvature k of a contour is the inverse of radius r of the nestling circle in a contour point
(k = 1/r).
Cycles
Protected subprograms for execution of repetitive machining operations on the → workpiece.
Data block
1. Data unit of the → PLC that → HIGHSTEP programs can access.
2. Data unit of the → NC: Data blocks contain data definitions for global user data. This data
can be initialized directly when it is defined.
Data word
Two-byte data unit within a → data block.
Diagnostics
1. Operating area of the control.
2. The control has a self-diagnostics program as well as test functions for servicing purposes:
status, alarm, and service displays
Dimensions specification, metric and inches
Position and pitch values can be programmed in inches in the machining program. Irrespective
of the programmable dimensions (G70/G71), the control is set to a basic system.
DRF
Differential Resolver Function: NC function which generates an incremental work offset in
Automatic mode in conjunction with an electronic handwheel.
Drive
The drive is the unit of the CNC that performs the speed and torque control based on the
settings of the NC.
Extended Functions
Function Manual, 10/2015, 6FC5397-1BP40-5BA3
Glossary
959