Beckhoff TS5066, Manual

Page: 23 / 31

PLC API
TS5066 23 Version: 1.0
E_Sync_TimeSync_Error_MaxDataAgeExceeded and bSynced =FALSE is displayed. iAgeOfDataLimit=0
deactivates the check. If the sender and receiver operate with different cycle times, iAgeOfDataLimit has to
be adjusted as described under fDataCycleTime .
iNoOfPeriodsForMeanDrift : The drift between sender and receiver used for regulation is determined as the
mean value between the last iNoOfPeriodsForMeanDrift values.
fDelayTimeOffset : Offset in [s] that is added to fCorrectionTime . Positive values refer to an additional
extrapolation into the future, e.g. for compensating runtime differences.
NOTE
Any changes of this value have a _direct_ influence on the correction time fCorrectionTime and therefore
on the extrapolated values (see FB_AxisExtrapolateValues [
}
17] or FB_AxisSync [
}
10] , for example). Ac-
cordingly, step changes in the kinematic variables used for control purposes caused by rapid changes in
fDelayTimeOffset must be avoided. The greater fDelayTimeOffset , the greater the deviation between the
values originally transferred and the extrapolated values. The parameter fMaxPositionDiff in the ST_Axi-
sExtrapolateParameters, for example, must be adjusted accordingly.
The following two parameters are particularly relevant for strong fluctuations in phase difference:
fSlope1Numerator : Part of the correction that is executed within the time
fSlope1denominator * fTaskCycleTime . In order to compensate the beat effects, the received cycle indices
have to be corrected by +/- 1 between two step changes. If a discontinuity occurs significantly earlier than
expected, the correction will not yet be completed, leading to a large difference to be corrected during the
next cycle. The parameters
fSlope1Numerator and fSlope1Denominator can be used to implement a
disproportionately large part of the correction directly after a discontinuity. fSlope1Numerator specifies which
part of the correction is implemented during the first period after a discontinuity, fSlope1Denominator
specifies the length of the period as a fraction of the expected time between the beat effects. The scaling
factor for the corrections during the remaining interval until the expected occurrence of the beat automatically
results from the requirement that 100% of the correction must have been applied at the expected time of
occurrence. The remaining part (1-
fSlope1Numerator ) of the correction is applied at time (1-
fSlope1Denominator )* fTaskCycleTime . Once the expected time of occurrence of the beat has been reached,
the correction remains constant.
The following slope values are used by default:
s1 = 0.95/0.5 = fSlope1Numerator / fSlope1Denominator
s2 = 0.05/0.5= (1- fSlope1Numerator )/ (1- fSlope1Denominator )
fSlope1Denominator : Specifies the time in fractions of the cycle time fTaskCycleTime , during which the
part of the correction specified through fSlope1numerator is applied.