Danfoss VLT FC 100 Series Programming Guide

14-03 Overmodulation
Option: Function:
[0] Off
[1]
*
On Select On [1] to set the overmodulation function for the output voltage, to obtain an output voltage of up to
15% higher than the mains voltage.
Select
Off [0] to select no overmodulation of the output voltage in order to avoid torque ripple on the motor
shaft.
14-04 PWM Random
Option: Function:
[0] *
Off
[1] On Select
On [1] to transform 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 modulated
output phases.
Select
Off [0] for no change of the acoustic motor switching noise.
3.14.3. Mains On/Off, 14-1*
Parameters for configuring mains failure monitoring and handling.
14-10 Mains Failure
Option: Function:
Select the function at which the frequency converter must act, when the threshold set in par.14-11 has been
reached or a
Mains Failure Inverse command is activated via one of the digital inputs (par. 5-1*).
[0]
*
No function The energy left in the capacitor bank will be used to "drive" the motor, but will be discharged.
[1] Controlled ramp-down The frequency converter will perform a controlled ramp-down. Par. 2-10 must be set to
Off [0].
[3] Coasting The inverter will turn off and the capacitor bank will back up the control card then ensuring a faster restart when
mains reconnected (at short power zags).
[4] Kinetic back-up The frequency converter will ride through by controlling speed for generative operation of the motor utilizing
the moment of inertia of the system as long as sufficient energy is present.
NB!
For best performance of controlled ramp-down and kinetic back-up par. 1-03
Torque Characteristics should be set to Compressor [0]
or
Variable Torque [1] (no automatic energy optimization should be active).
Illustration 3.2: Controlled Ramp-down - short mains failure. Ramping down to stop followed by ramping up to reference.
VLT
®
HVAC Drive Programming Guide 3. Parameter Description
MG.11.C5.02 - VLT
®
is a registered Danfoss trademark 125
3

Danfoss VLT FC 100 Series Specifications

General

Brand	Danfoss
Model	VLT FC 100 Series
Category	DC Drives
Language	English