Function:
This parameter is only active if in parameter 100
Con-
figuration
the selection made is
Speed regulation,
closed loop
. The FF function sends a larger or smaller
part of the reference signal outside the PID controller
in such a way that the PID controller only has an influ-
ence on part of the control signal. Any change to the
set point will thus have a direct effect on the motor
speed. The FF factor provides high dynamism when
changing the set point and less overswing.
Description of choice:
The required % value can be selected in the interval f
MIN
- f
MAX
. Values over 100 % are used if the set point
variations are only small.
452
Controller range
(pid contr. range)
Value:
0 - 200 %
10 %
Function:
This parameter is only active if
Speed regulation,
closed-loop
is made
in parameter 100
Configuration
.
The controller range (bandwidth) limits the output from
the PID controller as a % of motor frequency f
M,N
.
Description of choice:
The required % value can be selected for motor fre-
quency f
M,N
. If the controller range is reduced, the
speed variations will be less during initial tuning.
455
Frequency range monitor
(MON. FREQ. RANGE)
Value:
Disable
[0]
Enable
[1]
Function:
This parameter is used if warning 33
Out of frequency
range
must be turned off in the display in process con-
trol closed-loop. This parameter does not affect the
extended status word.
Description of choice:
Select
Enable
[1] to enable the readout in the display
if warning 33
Out of frequency range
occurs. Select
Disable
[0] to disable the readout in the display if warn-
ing 33
Out of frequency range
occurs.
456
Brake Voltage Reduce
(BRAKE VOL REDUCE)
Value:
0 - 25 V if 200 V device
0
0 - 50 V if 400 V device
0
Function:
The user sets the voltage by which the level for resistor
braking is reduced. It is only active when resistor in
parameter 400 is selected.
Description of choice:
The greater the reduction value, the faster the reaction
to a generator overload. Should only be used if there
are problems with overvoltage in the intermediate cir-
cuit.
457
Phase loss function
(PHASE LOSS FUNCT)
Value:
Trip (TRIP)
[0]
Autoderate & warning (AUTODERATE &
WARNING)
[1]
Warning (WARNING)
[2]
Function:
Select the function which is to be activated if the mains
imbalance becomes too high or if a phase is missing.
Description of choice:
At
Trip
[0] the adjustable frequency drive will stop the
motor within a few seconds (depending on drive size).
If
Autoderate & warning
[1] is selected, the drive will
export a warning and reduce the output current to 50
% of I
VLT,N
to maintain operation.
At
Warning
[2] only a warning will be exported when a
mains failure occurs, but in severe cases, other ex-
treme conditions might result in a trip.
VLT
®
2800 Series
= factory setting, () = display text, [] = value for use in communication via serial communication port
MG.27.A2.22 - VLT
®
is a registered Danfoss trademark
77
Prog
rammi
ng