Operating Instruction - Frequency Inverter 230V / 400V ... - opis.cz

15 V/f - CharacteristicThe sensor-less control in configurations 110 and 111 is based on the proportionalchange of output voltage compared to the output frequency according to the configuredcharacteristic.By setting the V/f-characteristic, the voltage of the connected 3-phase motor is controlledaccording to the frequency. The torque to be applied by the motor at the correspondingoperating point demands the control of the output voltage proportional tothe frequency. At a constant output voltage / output frequency ratio of the frequencyinverter, the magnetization is constant in the nominal operating range of the 3-phasemotor. The rating point of the motor or end point of the V/f-characteristic is set viathe guided commissioning with the parameter Cut-Off Voltage 603 and the parameterCut-Off Frequency 604.The lower frequency range, where an increased voltage is necessary for the start ofthe drive, is critical. The voltage at output frequency = zero is set with the parameterStarting Voltage 600. An increase in voltage deviating from the linear course of theV/f-characteristic can be defined by the parameters Voltage Rise 601 and Rise Frequency602. The percentage parameter figure is calculated from the linear V/fcharacteristic.Via the parameters Minimum Frequency 418 and Maximum Frequency419, the working range of the machine or the V/f-characteristic is defined.U 418 (FMIN) 419 (FMAX)Working range603 (UC)601 (UK)600 (US)602 (FK) 604 (FC) f(FMIN): Minimum Frequency 418, (FMAX): Maximum Frequency 419(US): Starting Voltage 600,(UK): Voltage Rise 601, (FK): Rise Frequency 602(UC): Cut-Fff Voltage 603, (FC): Cut-Off Frequency 604ParameterSettingsNo. Description Min. Max. Fact. sett.600 Starting Voltage 0.0 V 100.0 V 5.0 V601 Voltage Rise -100 % 200 % 10 %602 Rise Frequency 0 % 100 % 20 %603 Cut-Off Voltage 60.0 V 560.0 V 400.0 V604 Cut-Off Frequency 0.00 Hz 999.99 Hz 50.00 HzNote:The guided commissioning takes the parameterized rated motor valuesand reference data of the frequency inverter into account when it comesto pre-setting the V/f-characteristic. In the case of three-phase machines,the speed can be increased at a constant torque if the motorwinding can be switched over from star to delta connection. If the datafor delta connection indicated on the name plate of the three-phasemotor were entered, the cut-off frequency is increased automatically bythe square root of three.142 02/06