VLT
®
8000 AQUA
419 Setpoint 2
(SETPOINT 2)
Value:
Ref
MIN
- Ref
MAX
✭
0.000
Function:
Setpoint 2
is used in closed loop as the reference to
compare the feedback values with. See description
of parameter 417
Feedbackfunction
.
The setpoint can be offset with digital, analog or
bus signals, see
reference handling
.
Used in
Closed loop
[1] parameter 100
Configuration
and only if 2-zone minimum/maximum is selected
in parameter 417
Feedbackfunction
.
Description of choice:
Set the required value. The process unit is selected
in parameter 415
Process units
.
420 PID normal/inverse control
(PID NOR/INV. CTRL)
Value:
✭
Normal (NORMAL)
[0]
Inverse (INVERSE)
[1]
Function:
It is possible to choose whether the process
regulator is to increase/reduce the output frequency
if there is a deviation between reference/setpoint
and the actual process state.
Used in
Closed loop
[1] (parameter 100).
Description of choice:
If the AFD is to reduce the output frequency in case
the feedback signal increases, select
Normal
[0].
If the AFD is to increase the output frequency in case
the feedback signal increases, select
Inverse
[1].
421 PID anti windup
(PID ANTI WINDUP)
Value:
Off (DISABLE)
[0]
✭
On (ENABLE)
[1]
Function:
It is possible to choose whether the process regulator
is to continue regulating on a deviation even if it is not
possible to increase/reduce the output frequency.
Used in
Closed loop
[1] (parameter 100).
Description of choice:
The factory setting is
On
[1], which means that
the integration link is adjusted to the actual output
frequency if either the current limit, the voltage limit
or the max./min. frequency has been reached. The
process regulator will not be engaged again, until
either the deviation is zero or its prefix has changed.
Select
Off
[0] if the integrator is to continue
integrating to the deviation even if it is not possible
to remove the deviation by regulation.
NOTE
If
Off
[0] is selected, it will mean that when
the deviation changes its prefix, the integrator
will first have to integrate down from the level
obtained as a result of the former error, before any
change to the output frequency occurs.
422 PID start-up frequency
(PID START VALUE)
Value:
f
MIN
-f
MAX
(parameter 201 and 202)
✭
0 Hz
Function:
When the start signal comes, the AFD will react
in the form of
Open loop
[0] following the ramp.
Only when the programmed start frequency has
been obtained, will it change over to
Closed loop
[1]. In addition, it is possible to set a frequency that
corresponds to the speed at which the process
normally runs, which will enable the required process
conditions to be reached sooner.
Used in
Closed loop
[1] (parameter 100).
Description of choice:
Set the required start frequency.
NOTE
If the AFD is running at the current limit before
the desired start frequency is obtained, the
process regulator will not be activated. For the
regulator to be activated anyway, the start frequency
must be lowered to the required output frequency.
This can be done during operation.
✭
= factory setting. () = display text [] = value for use in communication via serial communication port
MG.80.A7.22 - VLT is a registered Danfoss trademark
138
Rosewood STP ST42 General (Operation and Maintenance Manual - Part 4:
Section 6.3 Manufacturers Manuals 6.3.33 Danfoss VLT Aquadrive 8000) Vendor Manual
QP Id: VM207
Active: 03/09/2013
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