Fantech VLT 2800 Series Instruction Manual page 69

be used to protect the application, like the ETR
will protect the motor if selected.
Description of choice:
Select how long the variable frequency drive should
maintain the output current at the current limit
I before it disconnects. At OFF parameter 409
LIM
Trip delay overcurrent, I
LIM
disconnection will not take place.
411 Switching frequency
(SWITCH FREQ.)
Value:
3000 - 14000 Hz (VLT 2803-75)
3000 - 10000 Hz (VLT 2880-82)
Function:
The set value determines the switching frequency of the
inverter. If the switching frequency is changed, this may
help to minimize 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 frequency.
Description of choice:
When the motor is running, the switching frequency
is adjusted in parameter 411 Switching frequency
until the frequency has been obtained at which the
motor is as low-noise as possible.
NOTE
The switching frequency is reduced
automatically as a function of the load.
See Temperature-Dependent Switching
Frequency under Special Conditions .
When LC-filter connected is selected in parameter
412, the switching frequency is 4.5 kHz.
412 Variable switching frequency
(VAR CARRIER FREQ.)
Value:
Without LC-filter (WITHOUT LC-FILTER)
LC-filter connected
(LC-FILTER CONNECTED)
= factory setting. () = display text [] = value for use in communication via serial communication port
68
is not working, i.e.
4500 Hz
4500 Hz
VLT® 2800 Series
Function:
The parameter must be set to LC-filter connected
if an LC-filter is connected between the adjustable
frequency drive and the motor.
Description of choice:
Select LC-filter connected [3] when an LC-filter
is connected between the adjustable frequency
drive and the motor.
NOTE
When the LC filter is selected, the switching
frequency is changed to 4.5 kHz.
413 Overmodulation function
(OVERMODULATION)
Value:
Off (OFF)
On (ON)
Function:
This parameter allows connection of the
overmodulation function for the output voltage.
Description of choice:
Off [0] 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 [1] means that an output voltage can be obtained
which is greater than the AC line voltage (up to 5 %).
414 Minimum feedback, FB
(MIN. FEEDBACK)
Value:
-100,000.000 - par. 415 FB
Function:
Parameter 414 Minimum feedback, FB
Maximum feedback, FB
display text to make it show the feedback signal in a
process unit proportionally to the signal on the input.
Description of choice:
[2]
Set the value to be shown on the display as the
minimum feedback signal value on the selected
[3]
feedback input (parameters 308/314 Analog inputs).
MG.28.A8.22 - VLT is a registered Danfoss trademark
MIN
MAX
and 415
MIN
are used to scale the
MAX
[0]
[1]
0.000