GE T2100 - Motor Torque; Motor Speed; Electrical Requirements

TheoryofOperation
andmotorwindingsisidenticaltoanACmotordrive.Thenumberofelectricalcycles
permechanicalrevolutionisequaltothenumberofrotorpolesdividedbytwo.
MotorTorque
Tocontrolmotortorque,itisnecessarytocontrolthecurrentthroughthemotor
windingssincetorqueisdirectlyproportionaltomotorcurrent.Rapidlyswitchingthe
powerdevicesonandofflimitstheeffectivevoltageappliedtothemotorwinding.
Usingafeedbackloop,avoltagecommandcontrolsthemotorcurrent.Thisiscalled
thecurrentlooporinnerloopofthedrive.
MotorSpeed
Controlofmotortorqueisonlyhalfofthemotorcontrolprocess,sincetheultimate
goalofamotordriveistoprovideanadjustablemotorspeed.Thesimplestspeed
controlloopconsistofasummingjunctiontodeterminethedifferencebetweenthe
desiredmotorspeedandtheactualmotorspeed,alongwithagainblockthatfeeds
intothecurrentloop.Thecurrentloopmaybeconsideredasingleblockwithvoltage
asaninputandmotorcurrentasanoutput.Theoverallfeedbackloopiscalledthe
velocitylooporouterloopofthedrive.Whilethissystemcontrolsmotorspeed,it
cannotcontroltheexactmotorspeedsincesomeerrorsignalisrequiredtodrivethe
currentloop.Theactualmotorspeedisdependentonthespeedcommand,theload,
theerrorgain,andthecharacteristicsofthemotoritself.
Addinganintegratortotheerroramplierallowsexactspeedcontrol.Anyspeederror
resultsinanoutputfromtheintegratorthatbuildswithtimeandcausesanoutput
tothecurrentloop.Thisloop,therefore,willseekzerospeederror.Thisisthetypeof
velocityloopusedintheT2100Treadmilldrive.
ElectricalRequirements
Thetwoblackwiresthatexitthesideoftheenclosuresupplypowertothedrive.The
powersourceshouldbesinglephase,200–240VAC,50–60Hz,16A.
Maximuminputcurrentis16A.
FusesshouldbeFLM20ASLOonly.Substitutingadifferentfusetypemaycause
areorsafetyhazard.
Theorangewirefromthesideoftheenclosureisconnectedtothesheetmetal
enclosureandshouldbeconnectedtothedesignatedterminalonthepowerterminal
block.DonotconnectthiswiretotheT2100Treadmillframewhichwouldcausea
safetyhazard.
Themotorwiresexitthroughtheexibleconduitontheleftsideoftheenclosure.
Thesewirescarrythepulsed320Vtothemotor.Besuretoobserveproperphasing
whenconnectingthesewires.Thedrivewillnotoperatewithincorrectphasing.
NOTE:
Ifthemotorisdisconnected,donotletthemotorwiresshorttoeachotherorany
otherpoint.Ifitrotates,themotorwillfunctionasagenerator,anditmaybe
damagedorcauseashockhazard.Thedrainwireshouldbeconnectedtothe
motorframe.Makesurethisconnectionissecure.
2021403-120F
T2100Treadmill
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