Drift Compensation - Siemens SINUMERIK 840Di sl Commissioning Manual

NC Commissioning with HMI Advanced
11.5 Axes and spindles
11.5.16

Drift compensation

Digital drives
Digital drives are not subject to drift or compensate for it automatically.
ADI4
As ADI4 does not support acyclic services on the PROFIBUS DP, drift compensation must
be performed manually by entering the appropriate compensation value in the following axial
machine data:
● MD36720 $MA_DRIFT_VALUE (basic drift value)
Manual drift compensation
Manual drift compensation is performed with the axis at zero speed as follows:
Requirements:
● Zero speed of the axis
● Axis enables pending
420
– Speed-controlled axis
The drift causes constant traversing of the axis. To compensate for the drift, the
compensation value is incremented/decremented step by step depending on the
direction of the drift until the axis reaches zero speed.
– Position-controlled axis
The drift causes a constant following error or position setpoint ≠ 0. To compensate for
the drift, the compensation value is incremented/decremented step by step depending
on the direction of the drift until following error or position setpoint = 0 is displayed.
HMI Advanced:
Operating area switchover > Diagnosis > Service displays > Service axis/spindle
WARNING
If the DSC function (Direct Servo Control) service is used for an axis, then no drift
compensation can be activated for this axis:
• MD32640 $MA_STIFFNESS_CONTROL_ENABLE (dyn. Stiffness control) = 1
Drift compensation causes extreme speed fluctuations during switch-on/off of the
DSC function.
Commissioning Manual, 05/2008, 6FC5397–4CP10–4BA0
Manual