Danfoss VLT 5000 Series User Manual

Function:
When the adjustable frequency drive registers an
overvoltage in the set time, cutting out is effected after
that time has passed.
Description of choice:
Select how long the adjustable frequency drive is to be
able to run at overvoltage before cutting out.
NOTE
If this value is reduced from the factory
setting, the unit may report a fault when
the mains voltage is turned on.
411 Switching frequency
(SWITCH FREQ.)
Value:
Depends on the unit output.
Function:
The set value determines the switching frequency of
the inverter. If the switching frequency is changed, this
may help to minimise possible acoustic noise from the
motor.
NOTE
The output frequency of the adjustable
frequency drive can never assume a value
higher than 1/10 of the switching frequen-
cy.
Description of choice:
When the motor is running, the switching frequency is
adjusted in parameter 411 until the frequency has
been obtained at which the motor is as low-noise as
possible.
See also parameter 446 - switching pattern.
NOTE
Switching frequencies higher than 3.0 kHz
(4.5 kHz for 60°C AVM) lead to automatic
derating of the maximum output of the ad-
justable frequency drive.
412
Output frequency dependent switching
frequency
(VAR CARRIER FREQ)
Value:
Not possible (DISABLE) [0]
Possible (ENABLE) [1]
Function:
This function makes it possible to increase the switch-
ing frequency at a falling output frequency. Used in
applications with square torque characteristics (cen-
trifugal pumps and fans) in which the load declines
depending on the output frequency. However, the
maximum switching frequency is determined by the
value set in parameter 411.
Description of choice:
Select Not possible [0] if a permanent switching fre-
quency is desired.
Set the switching frequency in parameter 411. If Pos-
sible [1] is selected the switching frequency will decline
at an increasing output frequency.
413 Overmodulation function
(OVERMODUL)
Value:
Off (OFF) [0]
On (ON) [1]
Function:
This parameter allows connection of the overmodula-
tion function for the output voltage.
Description of choice:
Off means that there is no overmodulation of the output
voltage, which means that torque ripple on the motor
shaft is avoided. This can be a good feature, e.g. on
grinding machines.
On means that an output voltage can be obtained
which is greater than the mains voltage (up to 15%).
VLT
®
5000 Series
= factory setting, () = display text, [] = value for use in communication via serial communication port
MG.51.C5.22 - VLT
p
is a registered Danfoss trademark. 129
Programming

Danfoss VLT 5000 Series Specifications

General

Brand	Danfoss
Model	VLT 5000 Series
Category	DC Drives
Language	English