Danfoss VLT FC 100 Operating Instructions Manual page 106

VLT HVAC Drive High Power Operating In-
structions
If one of the settings in parameter group 1-2* Motor
Data is changed, par. 1-30
Motor Poles , the advanced motor parame-
par. 1-39
ters, will return to default setting.
This parameter cannot be adjusted while the motor
is running.
1-71 Start Delay
Range:
0.0 s* [0.0 - 120.0 s]
1-73 Flying Start
Option:
[0] * Disabled
[1] Enabled
The Flystart Principle used for PM motors is based on a passive meas-
urement at speeds above 2%
Flystart Test Pulses Frequency ). Below that speed there are
par. 1-59
two options:
1. Either the motor is brought to a halt by using DC Brake (de-
fined in par. 2-01 DC Brake Current , par. 2-02 DC Braking
Time , par. 2-03 DC Brake Cut In Speed [RPM] or par. 2-04 DC
Brake Cut In Speed [Hz] ).
2. Change the method of speed and direction estimation to an
active scheme based on sending out test pules (defined in
Flystart Test Pulses Current and par. 1-59 Flystart
par. 1-58
Test Pulses Frequency ).
Current limitations of the Flystart Principle used for PM motors:
• The speed range is up to 100% Nominal Speed or the field
weakening speed (which ever is lowest).
Stator Resistance (Rs) to
Function:
The function selected in par. 1-80
Enter the time delay required before commencing acceleration.
Function:
This function makes it possible to catch a motor which is spinning freely due to a mains drop-out.
Flying Start is enabled, par. 1-71 Start Delay has no function.
When par. 1-73
Search direction for flying start is linked to the setting in par. 4-10
Clockwise [0]: Flying start search in clockwise direction. If not successful, a DC brake is carried
out.
Both Directions [2]: The flying start will first make a search in the direction determined by the
last reference (direction). If not finding the speed it will make a search in the other direction. If
not successful, a DC brake will be activated in the time set in par. 2-02
will then take place from 0Hz.
Select Disable [0] if this function is not required
Select Enable [1] to enable the frequency converter to "catch" and control a spinning motor.
The parameter is always set to [1] Enable when par. 1-10
ent.
Important related parameters:
• par. 1-58 Flystart Test Pulses Current
Flystart Test Pulses Frequency
• par. 1-59
Important parameters specifically when par. 1-10
• par. 2-01 DC Brake Current
• par. 2-02 DC Braking Time
DC Brake Cut In Speed [RPM]
• par. 2-03
DC Brake Cut In Speed [Hz]
• par. 2-04
of nominal (determined by
MG.11.F3.02 - VLT ® is a registered Danfoss trademark
Full AMA should be run without filter only while re-
duced AMA should be run with filter.
See section: Application Examples > Automatic Motor Adaptation in the
Design Guide.
Function at Stop is active in the delay period.
Motor Construction = [1] PM non sali-
Motor Construction = [1] PM non salient:
• PMSM with high back emf (>300VLL(rms)) and high winding
inductance(>10mH) needed more time for reducing short cir-
cuit current to zero and may be susceptible to error in estima-
tion.
• Current testing limited to a speed range up to 300Hz. For cer-
tain units the limit is 250Hz; all 200-240V units up to and in-
cluding 2.2kW and all 380-480V units up to and including
4kW.
• Current testing limited to a machine power size up to 22kW.
• Prepared for salient pole machine (IPMSM) but not yet verified
on those types of machine.
• An active measurement function is used to estimate the speed
at very low motor speeds. This function results in good accu-
racy in speed range up to 0-2% of the nominal motor speed.
6 How to Programme
Motor Speed Direction .
DC Braking Time . Start
105
6