Siemens SINUMERIK 840D sl Function Manual page 409

● $AA_QEC_TIME_1
● $AA_QEC_TIME_2
Extended Functions
Function Manual, 01/2008, 6FC5397-1BP10-3BA0
Recommended values for
– $AA_QEC_ACCEL_1: 20 mm/s
– $AA_QEC_ACCEL_2: 600 mm/s
– $AA_QEC_ACCEL_3: 1000 mm/s
The value of the parameter $AA_QEC_ACCEL_3 must be entered as appropriate to the
requirements; i.e. the neural network only works and learns optimally in this range. If a
higher acceleration is detected than the parameterized working area, the injection
amplitude that was determined during the defined maximum acceleration of the working
range is used. At high accelerations, this injection value is relatively constant.
The recommended values must only be changed if the compensation is insufficient in
these acceleration ranges. For further information, please refer to Section "Further
optimization and intervention options".
"Time constant for the neural QEC (decay time)"
With this, the decay time of the compensation setpoint pulse is set if adaptation of the
decay time is not used.
The optimum decay time must be ascertained manually using the circularity test at a
working point in the mid acceleration range. The procedure is described in detail in
connection with conventional friction compensation (Section "Commissioning of
conventional friction compensation") (analogous to machine data
MD32540 $FRICT_COMP_TIME (friction compensation time constant)).
With the recommended value (15 ms), it is possible to achieve good results.
Range of values: ≥ 0; recommended value: 0.015s
If the decay time adaptation is active, then $AA_QEC_TIME_1 determines the filter time
constant in the center of the operating range (i.e. with 0.5 * $AA_QEC_ACCEL_3).
"Compensation time constant for adaptation of compensation value decay time"
At a value of zero of less than or equal to $AA_QEC_TIME_1, no adaptation is
performed.
The decay time is usually constant over the entire working range. In rare cases however,
it can be advantageous to raise the decay time in the very small acceleration range, or to
lower it at high accelerations. For further information, please refer to Section "Further
optimization and intervention options".
Range of values: ≥ 0; recommended value: 0.015s (identical to $AA_QEC_TIME_1)
5.7 Neural quadrant error compensation
(= 2% of $AA_QEC_ACCEL_3)
2
(= 60% of $AA_QEC_ACCEL_3)
2
(maximum acceleration of working range)
2
Compensations (K3)
409