Danfoss VLT HVAC Drive FC 102 Operating Instructions Manual page 95

How to Programme
20-00 Feedback 1 Source
Option: Function:
[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.
NOTICE
If a feedback is not used, set its source to [0] No
Function. Parameter 20-20 Feedback Function determines
how the PID controller uses the 3 possible feedbacks.
20-01 Feedback 1 Conversion
Option: Function:
This parameter allows a conversion function
to be applied to feedback 1.
[0] Linear No effect on the feedback.
*
[1] Square root Commonly used when a pressure sensor is
used to provide flow feedback
(
flow ∝ pressure
[2] Pressure to Used in compressor applications to provide
temperature temperature feedback using a pressure sensor.
The temperature of the refrigerant is
calculated using the following formula:
Temperature =
where A1, A2 and A3 are refrigerant-specific
constants. Select the refrigerant in
20-30 Refrigerant. Parameter 20-21 Setpoint 1
through 20-23 Setpoint 3 allow the values of
A1, A2 and A3 to be entered for a refrigerant
that is not listed in 20-30 Refrigerant.
[3] Pressure to Used in applications for controlling the air
flow flow in a duct. A dynamic pressure
measurement (pitot tube) represents the
feedback signal.
Flow = Duct Area × Dynamic Pressure
Air Density Factor
×
See also 20-34 Duct 1 Area [m2] through
20-38 Air Density Factor [%] for setting of duct
area and air density.
[4] Velocity to Used in applications for controlling the air
flow flow in a duct. An air velocity measurement
represents the feedback signal.
Flow = Duct Area × Air Velocity
MG11F502
Operating Instructions
).
A 2
,
− A 3
ln Pe + 1 − A 1
Danfoss A/S © 08/2014 All rights reserved.
20-01 Feedback 1 Conversion
Option: Function:
See also 20-34 Duct 1 Area [m2] through
20-37 Duct 2 Area [in2] for setting of duct
area.
20-03 Feedback 2 Source
Option: Function:
See parameter 20-00 Feedback 1
Source for details.
[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
[105] Sensorless Pressure
20-04 Feedback 2 Conversion
Option: Function:
See parameter 20-01 Feedback 1
Conversion for details.
[0] Linear
*
[1] Square root
[2] Pressure to temperature
[3] Pressure to flow
[4] Velocity to flow
20-06 Feedback 3 Source
Option: Function:
See parameter 20-00 Feedback 1
Source for details.
[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
6 6
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