Programming; Switching Over The System Of Units (G70/G71/G700/G710) - Siemens SINUMERIK 840D Function Manual

Example: Increment evaluations for the 1st axis
● Metric:
MD31090 $MA_JOG_INCR_WEIGHT[ 0 ; AX1 ] = 0.001 mm
● Inch:
MD31090 $MA_JOG_INCR_WEIGHT[ 1 ; AX1 ] = 0.00254 mm ≙ 0.0001 inch
In this way, MD31090 does not have to be written at every inch/metric switchover.
Remaining distances are not accumulated during incremental traversing with JOG when the
system of units is changed, since all internal positions always refer to mm.
System of units for sag compensation
The system of units for sag compensation is configured using machine data:
MD32711 $MA_CEC_SCALING_SYSTEM_METRIC
Further information:
Function Manual Monitoring and Compensating; Compensations
2.3.3

Programming

2.3.3.1

Switching over the system of units (G70/G71/G700/G710)

Using the commands of G group 13 (inch/metric system of units) within a part program, you can
switch over between the metric and inch system of units.
Activation
In order that commands G700 and G710 are available, the extended system of units
functionality must be switched on (MD10260 $MN_CONVERT_SCALING_SYSTEM = 1).
Syntax
G70
G71
G700
G710
Meaning
G70:
Axes and spindles
Function Manual, 06/2019, A5E47437747B AA
G2: Velocities, setpoint / actual value systems, closed-loop control
Activating the inch system of units
The inch system of units is used to read and write geometrical data in units of length.
Technological data in units of length (e.g. feedrates, tool offsets, adjustable work offsets,
machine data and system variables) is read and written using the parameterized basic sys‐
tem.
G group: 13
Initial setting: Settable via MD20150 $MC_GCODE_RESET_VALUES
Effectiveness: Modal
2.3 System of units, metric/inch
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