Danfoss VLT HVAC Operating Instructions Manual

Also see for VLT HVAC: Instructions Operating instructions Design guide Instruction Instruction manual

Contents

Area Title Functions1 Mains input • Three-phase AC mains powersupply to the frequencyconverter2 Rectifier • The rectifier bridge convertsthe AC input to DC current tosupply inverter power3 DC bus • Intermediate DC-bus circuithandles the DC current4 DC reactors • Filter the intermediate DCcircuit voltage• Prove line transient protection• Reduce RMS current• Raise the power factorreflected back to the line• Reduce harmonics on the ACinput5 Capacitor bank • Stores the DC power• Provides ride-throughprotection for short powerlosses6 Inverter • Converts the DC into acontrolled PWM AC waveformfor a controlled variableoutput to the motor7 Output to motor • Regulated three-phase outputpower to the motor8 Control circuitry • Input power, internalprocessing, output, and motorcurrent are monitored toprovide efficient operationand control• User interface and externalcommands are monitored andperformed• Status output and control canbe providedTable 1.3 Frequency Converter Internal ComponentsIntroduction VLT® HVAC Drive Operating InstructionsMG11AH02 - VLT® is a registered Danfoss trademark 71 1