VLT
®
4000 VT
Programming
Description of choice:
If
Minimum
[0] is selected, the VLT AFD will compare
feedback 1
with
feedback 2
and regulate on the
basis of the lower feedback value.
Feedback 1 = Sum
of parameter 535
Bus feedback
1
and the feedback signal value of terminal 53.
Feedback 2 = Sum
of parameter 536
Bus feedback
2
and the feedback signal value of terminal 54.
If
Maximum
[1] is selected, the VLT AFD will compare
feedback 1
with
feedback 2
and regulate on the
basis of the higher feedback value.
If Sum [2] is selected, the VLT AFD will total
feedback
1
with
feedback 2
. Please note that the remote
reference will be added to Setpoint 1.
If
Difference
[3] is selected, the VLT AFD will
subtract
feedback 1
from
feedback 2
.
If
Average
[4] is selected, the VLT AFD will calculate the
average of
feedback 1
and
feedback 2
. Please note that
the remote reference will be added to the Setpoint 1.
If
2-zone minimum
[5] is selected, the VLT AFD will
calculate the difference between
Setpoint 1
and
feedback 1
as well as
Setpoint 2
and
feedback
2
. After this calculation, the VLT AFD will use
the larger difference. A positive difference, i.e.
a setpoint higher than the feedback, is always
larger than a negative difference.
If the difference between
Setpoint 1
and
feedback
1
is the larger of the two, parameter 418
Setpoint
1
will be added to the remote reference.
If the difference between
Setpoint 2
and
feedback 2
is the larger of the two, the remote reference will be
added to the parameter 419
Setpoint 2
.
If 2-zone maximum [6] is selected, the VLT AFD will
calculate the difference between
Setpoint 1
and
feedback 1
as well as
Setpoint 2
and
feedback 2
.
After the calculation, the VLT AFD will use the smaller
difference. A negative difference, i.e. one where
the setpoint is lower than the feedback, is always
smaller than a positive difference.
If the difference between
Setpoint 1
and
feedback 1
is the smaller of the two, the remote reference will
be added to the parameter 418
Setpoint 1
.
If the difference between
Setpoint 2
and
feedback 2
is the smaller of the two, the remote reference will
be added to parameter 419
Setpoint 2
.
418 Setpoint 1
(SETPOINT 1)
Value:
Ref
MIN
- Ref
MAX
✭
0.000
Function:
Setpoint 1
is used in closed loop as the reference to
compare the feedback values with. See description
of parameter 417
Feedback function
. The setpoint
can be offset with digital, analog or bus references,
see
Reference handling
. Used in
Closed loop
[1] parameter 100
Configuration
.
Description of choice:
Set the required value. The process unit is selected
in parameter 415
Process units
.
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
MG.40.A7.22 - VLT is a registered Danfoss trademark
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