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20-00 Feedback 1 Source
Option:
Function:
Up to three different feedback
signals can be used to provide the
feedback signal for the frequency
converter’s PID Controller.
This meter defines which input will
be used as the source of the first
feedback signal.
Analog input X30/11 and Analog
input X30/12 refer to inputs on the
optional General Purpose I/O board.
[0]
No function
[1]
Analog input 53
[2]
*
Analog input 54
[3]
Pulse input 29
[4]
Pulse input 33
[7]
Analog input X30/11
[8]
Analog input X30/12
[9]
Analog Input X42/1
[10]
Analog Input X42/3
[11]
Analog Input X42/5
[15]
Analog Input X48/2
[100] Bus feedback 1
[101] Bus feedback 2
[102] Bus feedback 3
[104] Sensorless Flow
Requires set up by MCT 10 Set-up
Software with sensorless specific
plug in.
[105] Sensorless Pressure
Requires set up by MCT 10 Set-up
Software with sensorless specific
plug in.
NOTE
If a feedback is not used, its source must be set to
No
Function
[0].
determines how the
three possible feedbacks will be used by the PID
Controller.
20-01 Feedback 1 Conversion
Option:
Function:
This meter allows a conversion function to be
applied to Feedback 1.
[0]
*
Linear
Linear
[0] has no effect on the feedback.
[1] Square root
Square root
[1] is commonly used when a
pressure sensor is used to provide flow
feedback
(
(
flow ∝ pressure)
).
[2] Pressure to
temperature
Pressure to temperature
[2] is used in
compressor applications to provide
temperature feedback using a pressure sensor.
20-01 Feedback 1 Conversion
Option:
Function:
The temperature of the refrigerant is
calculated using the following formula:
Temperature =
A2
(ln(Pe + 1) − A1) − A3
,
where A1, A2 and A3 are refrigerant-specific
constants. The refrigerant must be selected in
.
through
allow the values of A1, A2
and A3 to be entered for a refrigerant that is
not listed in
.
[3] Pressure to
flow
Pressure to flow is used in applications where
the air flow in a duct is to be controlled. The
feedback signal is represented by a dynamic
pressure measurement (pitot tube).
Flow = Duct Area × Dynamic Pressure
×
Air Density Factor
See also
20-34 Duct 1 Area [m2]
through
for setting of duct
area and air density.
[4] Velocity to
flow
Velocity to flow is used in applications where
the air flow in a duct is to be controlled. The
feedback signal is represented by an air
velocity measurement.
Flow = Duct Area × Air Velocity
See also
20-34 Duct 1 Area [m2]
through
20-37 Duct 2 Area [in2]
for setting of duct area.
20-02 Feedback 1 Source Unit
Option:
Function:
This meter determines the unit that is used for
this Feedback Source, prior to applying the
feedback conversion of
. This unit is not used by the PID
Controller.
[0]
*
None
[1]
%
[5]
PPM
[10]
1/min
[11]
RPM
[12]
Pulse/s
[20]
l/s
[21]
l/min
[22]
l/h
[23]
m³/s
[24]
m³/min
[25]
m³/h
[30]
kg/s
[31]
kg/min
[32]
kg/h
[33]
t/min
[34]
t/h
[40]
m/s
[41]
m/min
Parameter Description
VLT
®
HVAC Drive Programming Guide
MG.11.CC.02 - VLT
®
is a registered Danfoss trademark
129
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