Danfoss VLT 3000 Series Product Manual

Also see for VLT 3032: Service manual Product manual

Danfoss VLT 3000 Series Product Manual Manual pdf 140 page image

140 MG.30.A7.02 - VLT ® is a registered Danfoss trademarkOver-tempThe temperature inside the VLT® frequencyconverter is too high. Possible reasons:the ambient temperature is too high (max.40/45 °C), the VLT® frequency converter’scooling ribs are covered, or the VLT® fre-quency converter's fan is defective.• Reduce the ambient temperature byincreasing the ventilation.Uncover/clean the cooling ribs.Replace the fan.OverloadThe electronic VLT® protection is active.This means that the motor has consumedmore than 105% of rated VLT® frequencyconverter current for too long.• Reduce the motor load. If this is notpossible the application may require alarger VLT® frequency converter.Motor tripThe electronic motor protection is active.This means that the current consumed bythe motor at low speed has been too highfor too long.• The motor has been loadedexcessively at low speed.If the load cannot be changed,you must exchange the motor fora bigger one, or provide extra coolingof the existing motor.If so, the electronic motor protectioncan be de-activated in parameter 315.Fault messages Inverter faultThe VLT® power section is defective.OvervoltageThe voltage of the VLT® frequency conver-ter’s intermediate circuit (DC-voltage) is toohigh. Possible reasons: line voltage toohigh, transients on the line voltage, or re-generative motor operation.Note: When the VLT® frequency converteris stopped, repeated transients are charg-ing the intermediate circuit, as it supplies nopower to the motor.• If the fault indication is given whenthe speed is reduced, you can increasethe ramp-down time. If this is notpossible, the application may require aVLT® frequency converter with brake.If the fault indication is given in othersituations, the problem will be due tothe mains supply.UndervoltageThe voltage of the VLT® frequency conver-ter’s intermediate circuit (DC-voltage) is toolow. Possible reasons: line voltage too lowor defect in the VLT® frequency converter’scharging circuit/rectifier.• Check whether the line voltage is OK.OvercurrentThe peak current limit of the inverter hasbeen reached. This may be due to a short-circuit in the output of the VLT® frequencyconverter.• Check the motor and the motor cablefor ground failure.Ground faultGround failure on the VLT® frequency con-verter output. Another reason might be thatthe motor cable is too long.• Consult the data sheets for permittedcable length.Check the motor and the motor cablefor earth leakage.Fault messages