Danfoss VLT AutomationDrive FC 300 Programming Manual page 196

FC 300 Programming Guide
NB!
Switching frequencies higher than 5.0 kHz lead to automatic derating of the maximum output of the frequency converter.
14-03 Overmodulation
Option:
[0] Off
[1] * On
14-04 PWM Random
Option:
[0] * Off
[1] On
14-06 Dead Time Compensation
Option:
[0] Off
[1] * On
3.15.3 14-1* Mains On/Off
Parameters for configuring mains failure monitoring and handling. If a mains failure appears, the frequency converter will try to continue in a controlled
way until the power in the DC link has been exhausted.
14-10 Mains Failure
Par. 14-10 Mains Failure is typically used where very short mains interruptions (voltage dips) are present. At 100% load and a short voltage interruption,
the DC voltage on the main capacitors drops quickly. For larger drives it only takes a few milliseconds before the DC level is down to about 373 V DC
and the main IGBT cuts off and looses the control over the motor. When the mains is restored, and the IGBT starts again, the output frequency and
voltage vector does not correspond to the speed/frequency of the motor, and the result is normally an overvoltage or overcurrent, mostly resulting in
Mains Failure
a trip lock. Par. 14-10
Option:
Function:
On
Select [1] to connect the overmodulation function for the output voltage, to obtain an output
voltage up to 15% greater than the mains voltage.
Select Off [0] for no overmodulation of the output voltage, in order to avoid torque ripple on the
motor shaft. This feature may be useful for applications such as grinding machines.
Function:
No change of the acoustic motor switching noise.
Transforms the acoustic motor switching noise from a clear ringing tone to a less noticeable 'white'
noise. This is achieved by slightly and randomly altering the synchronism of the pulse width modu-
lated output phases.
Function:
No compensation.
Activates dead time compensation.
can be programmed to avoid this situation.
Function:
Function: Select the function to which the frequency converter must act when the threshold in
par. 14-11 Mains Voltage at Mains Fault
Par. 14-10 Mains Failure
Controlled ramp down:
The frequency converter will perform a controlled ramp down. If par. 2-10
or AC brake [2], the ramp will follow the Over Voltage Ramping. If par. 2-10
Resistor Brake
the ramp will follow the setting in par. 3-81
Controlled ramp down [1]:
After power-up the frequency converter is ready for start. Controlled ramp down and trip [2]: After
power-up the frequency converter needs a reset for starting.
®
MG.33.M8.02 - VLT is a registered Danfoss trademark
has been reached.
cannot be changed while motor is running.
Quick Stop Ramp Time
3 Parameter descriptions
3
Brake Function is Off [0]
Brake Function is [1]
.
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