Siemens SINUMERIK FM-NC Installation And Startup Manual page 101

03.96
Fig. 6-3
Example The user wishes to enter the linear velocity in m/min.
The internal physical quantity is mm/s.
The machine data must be entered as follows:
MD 10220: SCALING_USER_DEF_MASK = 'H4' (activation of new factor) and
MD 10230: SCALING_FACTORS_USER_DEF [2] = 16.6666667 (scaling factor
for linear velocity in m/min).
The machine data are automatically converted to these physical quantities after
input of the new scale and power ON. The new values are displayed on the
MMC and can then be saved.
The unit of the physical quantities for programming in the part program is
specified in the Programming Guide.
Internal
The internal control calculation resolutions are entered in MD 10200:
calculation INT_INCR_PER_MM (calculation resolution for linear positions) and
MD 10210: INT_INCR_PER_DEG (calculation resolution for angular
resolutions
positions).
The default value for this machine data is "1000". The control thus calculates as
standard in 1/1000 mm or 1/1000 degrees. If greater accuracy is required, only
these two machine data need to be changed. It is useful to enter machine data
in powers of 10 (100, 1000, 10000). If required, rounding (and thus also
falsification) of the internal values can only be achieved with finer units.
However, it is essential that the measuring system is adapted to this degree of
accuracy. The internal calculation resolution also determines the accuracy with
which positions and selected compensation functions are calculated. Changes
to the MD have no influence on the velocities and cycle times which can be
attained.
Display resolution
In MD 9004: DISPLAY_RESOLUTION, you can set the number of decimal
places after the decimal point for the position values on the operator panel.
Input and display The input value limitation depends on what values can be displayed and input
limit values on the operator panel.
This limit is reached at 10 digit positions plus decimal point plus sign.
 Siemens AG 2000 All Rights Reserved
SINUMERIK 840D Installation and Start-Up Guide (IAD) – 04.00 Edition
6 Assigning Parameters to the Control and the PLC Program
Input values for machine data
MD 10220
Scaling factor
activated?
yes
MD 10230
Scaling factor
Internal physical quantity
Changing physical quantities
1 m * 1000 mm * 1 min
[m/min] =
min * 1 m * 60 s
6.6 System data
no
Internal scaling
= 1000/60 [mm/s] = 16.666667
6
6-101