Interroll DL Series - Options and Accessories; Asynchronous Drum Motors with Frequency Inverters; Torque Depends on Input Frequency; Frequency Inverter Parameters

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Version 1.2 (08/2022) en
Translation of original operating instructions
Options and accessories
6 Options and accessories
6.1 Asynchronous drum motors with frequency inverters
6.1.1 Torque depends on input frequency
Operatingfrequency[Hz] 5 10 15 20 25 30-50 55 60 65 70 75 80
Available motor torque in %
Rated motor
frequency
50Hz 80 85 90 95 100 100 91 83 77 71
60Hz 75 80 85 90 95 100 100 100 92 86 80 75
Value1:Basedonaratedmotorfrequencyof50Hz(50-Hzmotorsshouldbeoperatedonlyupto70Hzinthe
speedrangeundereldcontrol.)
Value2:Basedonaratedmotorfrequencyof60Hz(60-Hzmotorsshouldbeoperatedonlyupto80Hzinthe
speedrangeundereldcontrol.)
ThetorquedependencydepictedinthegureaboveisexpressedasP=Txω. With a reduced operating frequency
ofbelow20/24Hz,themotortorqueisreducedbychangingheatdissipationconditions.Thepowerlossdissipationis
aresultoftheoilquantity,incontrasttostandardventilatedmotors.Forfrequenciesstartingat80...85/95100Hz,
the curve for the output torque does not have a hyperbolic shape, but is instead replaced with a quadratic function
whichistheresultoftheeectofthepull-outtorqueandthevoltage.Theoutput/frequencycharacteristicsofmost
frequencyinverterssuppliedwith3x400V/3x460Vcanbeparameterizedto400V/87Hzinordertoconnect
motorswith230V/50Hz.Thismaycreatefurtherlossesinthemotorandleadtoitsoverheatingifthemotoris
dimensionedwithinsucientpowerreserves.
6.1.2 Frequency inverter parameters
Clock frequency:
Ahighclockfrequencyleadstoabetterutilizationfactorofthemotor.Optimumfrequenciesare8or16kHz.
Parameters such as the quality of smooth running tests (motor is running smoothly) and noise development are also
aectedpositivelybyhighfrequencies.