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22-82 Work Point Calculation
Option:
Function:
pump curve, along with H
MIN
as described above,
allows the frequency converter to calculate the
reference point B and thus to plot the control
curve which will also include the System design
Working Point A.
Set point
Control Curve
n
DE
SIG
N
-f
D
ES
IG
N
n
RA
TE
D
-f
RA
TE
D
(head)
H
H
RATED
Par.
22-88
Q
DESIGN
Par.
22-89
H
MIN
D
B
C
A
Q
RATED
Par.
22-90
(flow)
Q
H
DESIGN
130BA387.11
22-84/
22-87
22-83/
Par.:
[0]
*
Disabled Work Point Calculation not active. To be used if
speed at design point is known (see ).
[1] Enabled Work Point Calculation is active. Enabling this
parameter allows the calculation of the unknown
System Design Working Point at 50/60 Hz speed,
from the input data set in
and
22-83 Speed at No-Flow [RPM]
Range:
Function:
Size
related
*
[ 0 - par.
22-85
RPM]
Resolution 1 RPM.
The speed of the motor at which flow Is
zero and minimum pressure H
MIN
is
achieved should be entered here in RPM.
Alternatively, the speed in Hz can be
entered in
. If
it has been decided to use RPM in
then
should also be used.
Closing the valves and reducing the
speed until minimum pressure H
MIN
is
achieved will determine this value.
22-84 Speed at No-Flow [Hz]
Range:
Function:
Size
related
*
[ 0.0 -
par.
22-86 Hz]
Resolution 0.033 Hz.
The speed of the motor at which flow has
effectively stopped and minimum
pressure H
MIN
is achieved should be
entered here in Hz. Alternatively, the
speed in RPM can be entered in
. If it has
been decided to use Hz in
then
22-84 Speed at No-Flow [Hz]
Range:
Function:
should also be used. Closing
the valves and reducing the speed until
minimum pressure H
MIN
is achieved will
determine this value.
22-85 Speed at Design Point [RPM]
Range:
Function:
Size
related
*
[ par.
22-83 -
60000.
RPM]
Resolution 1 RPM.
Only visible when
is set to
Disable
. The speed
of the motor at which the System
Design Working Point is achieved should
be entered here in RPM. Alternatively,
the speed in Hz can be entered in
22-86 Speed at Design Point [Hz]
. If it has
been decided to use RPM in
then
should also be used.
22-86 Speed at Design Point [Hz]
Range:
Function:
Size
related
*
[ par.
22-84 -
par. 4-19
Hz]
Resolution 0.033 Hz.
Only visible when
is set to
Disable
. The speed of
the motor at which the System Design
Working Point is achieved should be
entered here in Hz. Alternatively, the
speed in RPM can be entered in
22-85 Speed at Design Point [RPM]
. If it
has been decided to use Hz in
, then
should also be used.
22-87 Pressure at No-Flow Speed
Range:
Function:
0.000
*
[ 0.000 - par.
22-88 ]
Enter the pressure H
MIN
corresponding to Speed at No Flow
in Reference/Feedback Units.
Please also see
point D.
22-88 Pressure at Rated Speed
Range:
Function:
999999.999
*
[ par. 22-87 -
999999.999 ]
Enter the value corresponding
to the Pressure at Rated
Speed, in Reference/Feedback
Units. This value can be
defined using the pump
datasheet.
Please also see
point A.
Parameter Description
VLT
®
HVAC Drive Programming Guide
MG.11.CC.02 - VLT
®
is a registered Danfoss trademark
157
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