Danfoss VLT 2800 Design Manual page 80

Programming
function a selection can be made to determine how preset
references should be added to the external references.
There is also an independent local reference in parameter
003 Local reference, in which the resulting reference is set
pressing the [+]/[-] keys. When the local reference has
4 4
Illustration 4.7 Reference Handling
203 Reference range
Value:
Min. reference - Max reference (min - max)
-Max. reference - Max. reference
(-max - +max)
Function:
Select whether the reference signal must be positive or
whether it can be both positive and negative. The
minimum limit may be a negative value, unless a selection
has been made of Speed regulation, closed loop in
parameter 100 Configuration. If [3] Process regulation, closed
loop is selected for parameter 100 Configuration, select [0]
Min ref. - Max. ref..
Description of choice:
Select the required range.
Minimum reference, Ref
204
Value:
Parameter 100 Config. = Open loop
[0].-100,000.000 - par. 205 Ref
Parameter 100 Config. = [1]/[3] Closed
loop.Parameter 414 Minimum feedback -
par. 205 Ref
Function:
Minimum reference is an expression of the minimum
possible value of the total of all references. If [1] Speed
regulation, closed loop or [3] Process regulation, closed loop
78
MIN
MAX
MAX
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Design Guide
been selected, the output frequency range is limited by
parameter 201 Output frequency low limit, f
parameter 202 Output frequency high limit, f
The local reference unit depends on the selection in
parameter 100 Configuration.
is selected in parameter 100 Configuration, the minimum
reference is limited by parameter 414 Minimum feedback.
Minimum reference is ignored if the local reference is
[0]
active.
The reference unit is defined in Table 4.1.
[1]
Parameter 100 Configuration
[0] Open loop
[1] Speed reg, closed loop
[3] Process reg, closed loop
Description of choice:
The minimum reference is preset if the motor has to run at
a minimum speed, regardless of whether the resulting
reference is 0.
205
Value:
Parameter 100 Config. = [0] Open
loop.Parameter 204 Ref
0.000 Hz
Parameter 100 Config. = [1]/[3] Closed
loop. Parameter 204 Ref
0.000
415 Max. feedback
rpm/par 416
Function:
The maximum reference gives the highest value that can
be assumed by the sum of all references. If [1]/[3] Closed
loop is selected in parameter 100 Configuration the
Maximum reference, Ref
MAX
- 590.000 Hz
MIN
- Parameter
MIN
and
MIN
.
MAX
Unit
Hz
RPM
Parameter 416
50.000
Hz
50.000
rpm/par 416
MG27E402