Electrolux W565H - Motor and Control System; Motor Control Unit Functionality

Motorandmotorcontrol
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6Motorandmotorcontrol
Takecarewhenmeasuringthemotorcontrolsystemsinceallcomponentshaveapotentialdifferenceof
approximately300Vinrelationtoprotectiveearthandneutral.Thecomponentswillcontaindangerous
voltageswhenthegreenLEDonthemotorcontrolboardison.Themotorcontrolsystemwillremainlivefor
30-60secondsaftercuttingthepowertothemachineandthemotorhasstoppedrunning.
6.1Motorcontrolunit
Themotorcontrolunitcommunicateswiththecontrolsystemviaaserial(input/output)interface.
Withtheaidofthemotorcontrolunitthecontrolsystemcancontrolnotonlythespeedofthemotor
atanygivenpoint,butalsotheaccelerationordecelerationrateatwhichthemotoristoachievethe
speedrequired.Themotorcontrolunitconstantlyfeedsinformationoncurrentstatus(bothnormal
statusandonanyabnormalitiesarising)backtothecontrolsystem.
Themotorcontrolunitcanalsosupplydataonthedifferenttorqueandeffectofthemotorat
constantspeedwhenacceleratinganddeceleration.Thesedataareusedbothforcalculatingthe
weightoftheloadandfordetectinganyunbalance.
Thevoltageonthemotorcontrolcircuithasapotentialdifferenceofapprox.300Vinrelationtoincoming
neutralandearth.Becauseofthis,becarefulwhenmeasuring.Useunearthedoscilloscopes.Ifthemotor
controlunithasagreenLED,thiswillremainlitforaslongastherearehazardousvoltagespresentin
components.