Siemens SINUMERIK 840Di Function Manual page 392

Detailed Description
2.2 Metric/inch measuring system
Data, for which no unique physical units are defined, is not converted automatically.
This includes:
• R parameters
• GUDs (Global User Data)
• LUDs (Local User Data)
• PUD (Program global User Data)
• Analog inputs/outputs
• Data exchange via FC21
The user is prompted to take the current valid measuring system:
MD10240 $MN_SCALING_SYSTEM_IS_METRIC
into account.
The current measuring system setting can be read at the PLC interface via the "inch
measuring system" signal:
DB10 DBX107.7.
Signal:
DB10 DBB71 (inch/metric measuring system modification counter)
can be used for reading the "measuring system modification counter".
User tool data
Additional machine data sets are introduced for user-defined tool data:
MD18094 $MN_MM_NUM_CC_TDA_PARAM
and cutting edge data:
MD18096 $MN_MM_NUM_CC_TOA_PARAM:
MD10290 $MN_CC_TDA_PARAM_UNIT [MM_NUM_CC_TDA_PARAM]
MD10292 $MN_CC_TOA_PARAM_UNIT [MM_NUM_CC_TOA_PARAM]
A physical unit can be configured using these machine data. All lengthrelated userdefined
tool data are automatically converted to the new measuring system according to the input on
switchover.
Reference point
The reference point is retained. It is not necessary to repeat referencing.
Input resolution and computational resolution
The input/computational resolution is set in the control via machine data:
MD10200 $MN_INT_INCR_PER_MM.
2-18
Velocities, Setpoint/Actual-Value Systems, Closed-Loop Control (G2)
Function Manual, 08/2005 Edition, 6FC5397-0BP10-0BA0