Commissioning - Siemens SINUMERIK 840D Function Manual

● Data backup with system of units identifier INCH/METRIC (see "Commissioning
(Page 41)")
● Automatic data conversions when the system of units is changed, e.g. for:
– Work offsets
– Compensation data (EEC, QEC)
– Tool offsets
– ...
For compatibility reasons, the extended system of units functionality must be activated using a
machine data (see "Commissioning (Page 41)").
2.3.2

Commissioning

NC-specific machine data
Basic system
The basic system to be used by the controller for the scaling of length-dependent physical
variables for data input/output is specified via the machine data:
MD10240 $MN_SCALING_SYSTEM_IS_METRIC
Value
0 (= FALSE)
1 (= TRUE)
The system must be powered up again after changing this machine data as otherwise
associated machine data, which have physical units, will be incorrectly scaled.
The following procedure must be complied with:
● Changing the MD using manual entry:
– 1. Power up the system.
– 2. Machine data with physical units: Enter a value.
● The MD is changed using machine data:
– 1. Power up the system.
– 2. Load the machine data file once again so that the new physical units are taken into
When changing MD10240, Alarm 4070 "Normalizing machine data has been changed" is
output.
Note
When changing over the system of units at a control system, all length-related data must be
converted consistently and completely into the other measuring system.
Axes and spindles
Function Manual, 06/2019, A5E47437747B AA
G2: Velocities, setpoint / actual value systems, closed-loop control
Meaning
Data relating to length is interpreted as inch data.
Data relating to length is interpreted as metric data.
account.
2.3 System of units, metric/inch
41