Danfoss FC 103 Instruction Manual

Also see for VLT FC 103: Service guide Installation guide Installation guide Operating guide Installation guide

Contents

Danfoss FC 103 Instruction Manual Manual pdf 31 page image

7. 1-40 Back EMF at 1000 RPMEnter line-to-line back EMF of PM Motor at1000 RPM mechanical speed (RMS value). BackEMF is the voltage generated by a PM motorwhen no drive is connected and the shaft isturned externally. Back EMF is normally specifiedfor nominal motor speed or for 1,000 RPMmeasured between two lines. If the value is notavailable for a motor speed of 1000 RPM,calculate the correct value as follows: If back EMFis, e.g., 320 V at 1800 RPM, it can be calculated at1000 RPM as follows: Back EMF = (Voltage /RPM)*1000 = (320/1800)*1000 = 178. This is thevalue that must be programmed for 1-40 BackEMF at 1000 RPM.Test Motor Operation1. Start the motor at low speed (100 to 200 RPM). Ifthe motor does not turn, check installation,general programming and motor data.2. Check if start function in 1-70 PM Start Mode fitsthe application requirements.Rotor detectionThis function is the recommended choice for applicationswhere the motor starts from standstill, e.g., pumps orconveyors. On some motors, an acoustic sound is heardwhen the impulse is sent out. This does not harm themotor.ParkingThis function is the recommended choice for applicationswhere the motor is rotating at slow speed, e.g.,windmilling in fan applications. 2-06 Parking Current and2-07 Parking Time can be adjusted. Increase the factorysetting of these parameters for applications with highinertia.Start the motor at nominal speed. If the application doesnot run well, check the VVCplus PM settings. Recommen-dations for different applications can be seen in Table 5.6.Application SettingsLow inertia applicationsILoad/IMotor <51-17 Voltage Filter Time Const. to beincreased by factor 5 to 101-14 Damping Gain should bereduced1-66 Min. Current at Low Speedshould be reduced (<100%)Low inertia applications50>ILoad/IMotor >5Keep calculated valuesHigh inertia applicationsILoad/IMotor > 501-14 Damping Gain, 1-15 Low SpeedFilter Time Const. and 1-16 HighSpeed Filter Time Const. should beincreasedHigh load at low speed<30% (rated speed)1-17 Voltage Filter Time Const. shouldbe increased1-66 Min. Current at Low Speedshould be increased (>100% for aprolonged time can overheat themotor)Table 5.6 Recommendations for Different ApplicationsIf the motor starts oscillating at a certain speed, increase1-14 Damping Gain. Increase the value in small steps.Depending on the motor, a good value for this parametercan be 10% or 100% higher than the default value.Starting torque can be adjusted in 1-66 Min. Current at LowSpeed. 100% provides nominal torque as starting torque.5.4.5 Automatic Energy Optimization (AEO)NOTICE!AEO is not relevant for permanent magnet motors.Automatic Energy Optimization (AEO) is a procedure thatminimizes voltage to the motor, reducing energyconsumption, heat, and noise.To activate AEO, set parameter 1-03 Torque Characteristicsto [2] Auto Energy Optim. CT or [3] Auto Energy Optim. VT.Commissioning Instruction ManualMG16E322 Danfoss A/S © Rev. 2014-04-10 All rights reserved. 295 5