Siemens SINUMERIK 840C - Manual (Page 266)

09.95 6 NC Machine Data (NC MD), NC Setting Data (NC SD)
6.5 Spindle-specific MD (spindle data)
The set acceleration must not exceed the available acceleration reserves of the drive in
position control mode as this will result in large system deviations which are too high and
which will cause the drive to come to a standstill (with alarms 156*, 116*, 2014*).
In the parameterization of the maximum acceleration MD 478* of asynchronous main spindle
drive, please make sure that the available driving torque is reduced above the field weakening
range.
The run-up time of the drive must be measured against the set spindle maximum speed to
work out the possible setting values.
MD 478* is calculated from the measured run-up time according to the following example:
• Measure the minimum possible run-up time against the maximum spindle speed:
Select spindle mode, switch over gears if necessary
Set MD 419* for the gear state to 0 or to the minimum permissible value
M3/4 to the set maximum speed Nmax, e.g. 2000 rev/min
Measure the run-up time T according to the diagram
• The measured time can be entered directly into MD 478* and following. In so doing, a
certain reserve (10-50%) should be added to the measured value according to the
expected load.
Time constant setpoint filter (as from SW 2) 486*
Default value Lower input limit Upper input limit Units
55 0
1 000
16 000 (as from SW 4)
0.1 ms
Active
at once
Active: Immediately
The feed forward control parameter ”Time constant setpoint filter” is necessary in order to
also enable all the functions of dynamic feed forward control for the spindles.
The time constant is used to match the behaviour against time of the defined setpoint to the
dynamics of the drive.
When axes and spindles are linked, e.g., with ELG or synchronous spindle mode, the drives
involved must be set to the same dynamic response. The machine data in this case can be
altered to any values up to 0. The optimum setting for normal spindle modes is the standard
setting in the table above.
Note: As from SW 4, for 8 gear stages
P component compensatory controller 1) 487*
Default value Lower input limit Upper input limit Units
0 0 16 000 1
Active on
Reset
Note: As from SW 4, for 8 gear stages
I component compensatory controller 1) 488*
Default value Lower input limit Upper input limit Units
0 0 16 000 1
Active on
Reset
Note: As from SW 4, for 8 gear stages
_______
1) As from SW 3
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SINUMERIK 840C (IA)