gefran TPD32-EV-...-4B - Procedure of Calculation for Initial Diameter

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6.16.3.9 Procedure of calculation for initial diameter
Thecalculationisbasedonthemeasurementofthedancermovementfromthelowerfullrangepositiontoits
centralworkingposition,andonthemeasurentoftheangularmovementofthecoilduringthedrawingphase.
Forthatreason,duringthisperiod,makesurethatthegearmantainingthematerialblocked.Forthisreasonit
isnecessarytoenabletheregulationofthenip-rolldrivewithspeedreference=0.
Iflinenip-rollsarecontrolledbydancersorloadcells,itisnecessarytocarryoutthediametercalculationofthe
winders/unwindersrst,thenthegear.
TheparameterPI central v sel mustbesetat0toavoidPI output PID beingsetautomaticallyatapredenedvalue.
BringingthedigitalinputprogrammedasDiameter calctoahighlogiclevel(+24V),ifthedriveisenabled,
willstarttheprocedures.Duringthisphase,theparametersEnable PI PID andEnable PD PID areautomati-
callydisabled.
Theregulationveriesthesignalcomingfromthedancerpotentiometer.Ifthisishigherthanwhatisalready
setinMax deviation,themotorbeginsfollowingthespeedreferencesetinPositioning speed inordertowind
thematerialandbringthedancertoitscentralpositionofworking.
ThepolarityofthereferenceassignedtoPositioning speed willbewinder/unwinderequaltotheoneworking
asawinder.
Iftheinitialregulationveriesthatthesignalcomingfromthepotentiometerofthedancerislowerthanwhat
alreadysetinMax deviation,themotorstartsrunningwithspeedreferencesetinPositioning speed inorderto
unwindthematerialandbringthedanceronthepointidentiedbyMax deviation,atthispointthereference
willbeinvertedtobringthedancertoitscentralposition.
Whenthedancerhasreachedthecentralposition,theparameterPI output PID willbesetatavalueinversely
proportionaltothediameterandthedigitaloutputDiameter calc st,thatindicatestheendofdiametercalcula-
tion,willbebroughttohighlogicallevel.
Atthispoint,ifEnable PI PID and/orEnable PD PID areenabled,thesystempassesautomaticallyinregulation.
ForthisreasongenerallythedigitalinputsprogrammedasDiameter calc andEnable PI PID and/orEnable
PD PID willbebroughttohighlogiclevelatthesametime.
TheoutputsignalDiametercalcstcanbeusedtoresetthecommandDiameter calc (thiscommandwillbe
activatedontherisingedgeofthedigitalinput).Forthatreason,itmustbebroughttohighlogicallevelafter
thesupplyoftheregulationpartofthedriveandresetoncetheinitialcalculationphasehasnished.
ThevalueofPI output PID willbecalculatedwiththefollowingformula:
PI output PID =(Min diameter x PI top lim)/Valueofthecalculateddiameter
TheparametersPI top limit andPI bottom limit inthemenuPI controls havetobesetaccordingtothemax.
andmin.diameteroftheroll.Forbetterexplanation,pleaserefertoparagraph6.16.3.10“Applicationexamples”.