Siemens SINUMERIK 840D sl Function Manual page 443

Figure 5-34
In special cases, it might be necessary to reparameterize the error measuring times:
● Setting of very extreme values for the QEC compensation time constant. Experience
● Parameterization of the error measuring times with adaptation of the decay time of the
Extended Functions
Function Manual, 03/2009, 6FC5397-1BP10-4BA0
Dependency of error measuring time on acceleration rate
indicates that it is not useful to set an error measuring time of less than 10ms or more
than 200ms.
compensation value
If the adaptation of the decay time of the compensation value is active (see above), the
following rule of thumb is applicable to the parameterization of the error measuring time
for acceleration range 1:
$AA_QEC_MEAS_TIME_1 = 3 * $AA_QEC_ TIME_2
Example:
Decay time ($AA_QEC_TIME_1) = 10ms
Adaptation of decay time ($AA_QEC_TIME_2) = 30ms
The above rule of thumb produces an error measuring time for acceleration range 1 of:
$AA_QEC_MEAS_TIME_1 = 3 * 30ms = 90ms
Without decay time adaptation, the calculated setting for $AA_QEC_MEAS_TIME_1
would be merely 6 * 10ms = 60ms.
Compensations (K3)
Neural quadrant error compensation
443