Danfoss vlt hvac drive fc 102 Operating Instructions Manual

Also see for VLT HVAC Drive FC 102: Operating instructions Service guide Programming guide Installation guide Installation guide

Contents

1-71 Start DelayRange: Function:00s*[0 -120 s]When the frequency converter receives the startcommand, it delays the motor start for theperiod of time specified in this parameter.The function selected in parameter 1-80 Functionat Stop is active in the delay period.1-73 Flying StartOption: Function:This function makes it possible to catch a motorwhich is spinning freely due to a mains drop-out.When parameter 1-73 Flying Start is enabled,parameter 1-71 Start Delay has no function.Search direction for flying start is linked to thesetting in parameter 4-10 Motor Speed Direction.[0] Clockwise: Flying start search in clockwisedirection. If not successful, a DC brake is carriedout.[2] Both Directions: The flying start first makes asearch in the direction determined by the lastreference (direction). If not finding the speed, itmakes a search in the other direction. If notsuccessful, a DC brake is activated in the time setin 2-02 DC Braking Time. Start then takes placefrom 0 Hz.[0] Disabled Select [0] Disable if this function is not required[1] Enabled Select [1] Enable to enable the frequency converterto catch and control a spinning motor.The parameter is always set to [1] Enable when1-10 Motor Construction = [1] PM non salient.Important related parameters:• 1-58 Flystart Test Pulses Current• 1-59 Flystart Test Pulses Frequency• 1-70 PM Start Mode• 2-06 Parking Current• 2-07 Parking Time• 2-03 DC Brake Cut In Speed [RPM]• 2-04 DC Brake Cut In Speed [Hz]• 2-06 Parking Current• 2-07 Parking TimeThe flystart function used for PM motors is based on aninitial speed estimation. The speed is always estimated asthe first thing after an active start signal is given. Based onthe setting of 1-70 PM Start Mode the following happens:1-70 PM Start Mode = [0] Rotor Detection:If the speed estimate comes out as greater than 0 Hz, thefrequency converter catches the motor at that speed andresume normal operation. Otherwise, the frequencyconverter estimates the rotor position and start normaloperation from there.1-70 PM Start Mode = [1] Parking:If the speed estimate comes out lower than the setting in1-59 Flystart Test Pulses Frequency then the Parking functionis engaged (see 2-06 Parking Current and 2-07 ParkingTime). Otherwise, the frequency converter catches themotor at that speed and resume normal operation. Referto description of 1-70 PM Start Mode for recommendedsettings.Current limitations of the flystart principle used for PMmotors:• The speed range is up to 100% nominal speed orthe field weakening speed (which ever is lowest).• PMSM with high back EMF (>300 VLL(rms)) andhigh winding inductance(>10 mH) needed moretime for reducing short circuit current to zero andmay be susceptible to error in estimation.• Current testing limited to a speed range up to300 Hz. For certain units the limit is 250 Hz; all200-240 V units up to and including 2.2 kW andall 380-480 V units up to and including 4 kW.• Current testing limited to a machine power sizeup to 22 kW.• Pred for salient pole machine (IPMSM) but not yetverified on those types of machine.• For high-inertia applications (i.e. where the loadinertia is more than 30 times larger than themotor inertia) a brake resistor is recomended toavoid overvoltage trip during high speedengagement of the flystart function.How to Programme VLT HVAC Drive FC 102 Operating InstructionsMG11F402 - Rev. 2013-12-16 936 6