Metric/Inch Measuring System; Conversion Of Basic System By Parts Program - Siemens SINUMERIK 828D Function Manual

G2: Velocities, setpoint / actual value systems, closed-loop control

7.3 Metric/inch measuring system

7.3 Metric/inch measuring system
7.3.1

Conversion of basic system by parts program

Programmable switchover in the measuring system
The basic system can be switched over within a part program via the G functions G70/G71/G700/G710 (G group
13). The programmed measuring system (G70/G71/G700/G710) and the basic system may be identical or
different at any time. When the measuring system is switched over within a particular section of the part program,
this would enable an inch thread to be processed on a workpiece within a metric basic system, for example.
The following section of the part program is executed in "metric" in the basic system:
MD10240 $MN_SCALING_SYSTEM_IS_METRIC = 1
Program code
N100 G71
....
N200 G70
...
N300
...
Initial state of the G functions
The initial state for the G functions can be set via the following machine data on a channel-specific basis:
MD20150 $MC_GCODE_RESET_VALUES[12] (reset position for G group 13)
When changing the measuring system via the HMI user interface, the reset position is automatically
preconfigured for compatibility with the new measuring system via G700 or G710.
Displaying length-related data on the HMI
Length-related data is displayed on the HMI in the configured basic system
MD10240 $MN_SCALING_SYSTEM_IS_METRIC (metric basic system).
The following length-related data is displayed in the configured basic system:
• Machine data
• Data in the machine coordinate system
• Tool data
• Work offsets
The following length-related data is displayed in the programmed measuring system:
• Data in the workpiece coordinate system
340
Comment
; Switchover to metric processing
; The conversion factor does not come into effect because the
; programmed
measuring system does not differ from the basic system.
; Metric processing
; Switchover to processing in inches
; The conversion factor comes into effect.
; Machining in inches
; Switchover to metric processing
; Metric processing
Function Manual, 09/2011, 6FC5397-0BP40-2BA0
Basic Functions