Siemens sinumerik 840D sl Function Manual page 518

Optimizing the control response
If the control response of the axis is too rigid due to the velocity feedforward control, the
control response can be optimized with the following axis-specific NC machine data:
• MD32410 $MA_AX_JERK_TIME (time constant for the axial jerk filter).
• MD32610 $MA_VELO_FFW_WEIGHT (feedforward control factor for speed)
(840D)
The velocity filters of the SIMODRIVE 611D drive provide an additional means of damping:
• MD1502 $MD_SPEED_FILTER_1_TIME (time constant for speed setpoint filter 1)
• MD1503 $MD_SPEED_FILTER_2_TIME (time constant for speed setpoint filter 2)
(840Di)
The velocity filters of the SIMODRIVE 611 universal/ E and POSMO SI, CD, CA drives
provide an additional means of damping:
• Parameter 1502: (time constant for speed setpoint filter 1)
• Parameter 1503: (time constant for speed setpoint filter 2)
Caution
Every damping measure implemented contributes to increasing the overall time constant of
the control loop!
You will find a complete description of the velocity feedforward control in:
References:
/FB2/ Functions Manual Extended Functions, Compensations (K3), Following Error
Compensation (Feedforward Control)
Special functions: Clearance Control (TE1)
Function Manual, 11/2006, 6FC5397-2BP10-2BA0
Detailed description
2.2 Clearance control
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