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The following table can be used to help guide which design type should be selected:NEMA Electrical Design StandardsPolyphaseCharacteristicsDesign AHigh locked rotortorque and highlocked rotor currentDesign BNormal locked rotortorque and normallocked rotor currentDesign CHigh locked rotortorque and normallocked rotor currentDesign DHigh locked rotortorque and high slipDesign ENormal locked rotortorque and current,low slipLockedRotorTorque(PercentRated LoadTorque)70-27570-275200-28527575-190Pull-UpTorque(PercentRated LoadTorque)65-19065-190140-195NA60-140BreakdownTorque(PercentRated LoadTorque)175-300175-300190-225275160-200LockedRotorCurrent(PercentRatedLoadCurrent)Notdefined600-700600-700600-700800-1000Slip0.5-5%0.5-5%1-5%5-8%0.5-3%Typical ApplicationsFans, blowers, centrifugal pumpsand compressors, motor-generatorsets, etc., where starting torquerequirements are relatively lowFans, blowers, centrifugal pumpsand compressors, motor-generatorsets, etc., where starting torquerequirements are relatively lowConveyors, crushers, stirringmotors, agitators, reciprocatingpump and compressors, etc.,where starting under load isrequiredHigh peak loads with or withoutflywheels such as punch presses,shears, elevators, extractors,winches, hoists, oil-well pumpingand wire-drawing motorsFans, blowers, centrifugal pumpsand compressors, motor-generatorsets, etc., where starting torquerequirements are relatively lowRelativeEfficiencyMedium orhighMedium orhighMediumLowHigh-13-