14-01 Switching Frequency
Option:
Function:
[1]
1.5 kHz
[2]
2.0 kHz
[3]
2.5 kHz
[4]
3.0 kHz
[5]
3.5 kHz
[6]
4.0 kHz
[7]
*
5.0 kHz
[8]
6.0 kHz
[9]
7.0 kHz
[10]
8.0 kHz
[11]
10.0 kHz
[12]
12.0 kHz
[13]
14.0 kHz
[14]
16.0 kHz
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 parameter 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 MCT10 with
sensorless specific plug in.
[105] Sensorless Pressure
Requires set up by MCT10 with
sensorless specific plug in.
NOTE
If a feedback is not used, its source must be set to
No
Function
[0]. Par. 20-20
Feedback Function
determines
how the three possible feedbacks will be used by the
PID Controller.
20-01 Feedback 1 Conversion
Option:
Function:
This parameter 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
temper-
ature
Pressure to temperature
[2] is used in compressor
applications to provide temperature feedback using
a pressure sensor. 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
par. 20-30
Refrigerant
. Par. 20-21
Setpoint 1
through
par. 20-23
Setpoint 3
allow the values of A1, A2 and
A3 to be entered for a refrigerant that is not listed in
par. 20-30
Refrigerant
.
[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 par. 20-34
Duct 1 Area [m2]
through
par. 20-38
Air Density Factor [%]
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 measure-
ment.
Flow = Duct Area × Air Velocity
See also par. 20-34
Duct 1 Area [m2]
through
par. 20-37
Duct 2 Area [in2]
for setting of duct area.
20-02 Feedback 1 Source Unit
Option:
Function:
This parameter determines the unit that is used for
this Feedback Source, prior to applying the
feedback conversion of par. 20-01
Feedback 1
Conversion
. This unit is not used by the PID Control-
ler.
[0]
*
[1]
%
[5]
PPM
[10]
1/min
[11]
RPM
[12]
Pulse/s
[20]
l/s
[21]
l/min
[22]
l/h
How to Programme the Frequ...
VLT
®
HVAC Drive Operating Instructions
MG.11.AD.02 - VLT
®
is a registered Danfoss trademark
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