Danfoss VLT HVAC FC 100, Instruction Manual

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[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 adjustable
frequency drive’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
[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 temperature
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 for-
mula:
Temperature =
A
2
( ln ( Pe
+ 1) −
A
1)
− A 3
, where A1, A2 and A3 are refrigerant-specific con-
stants. 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).
VLT HVAC Low Harmonic Drive Instruction
Manual 6 How to Program the Low Harmonic Drive
MG.16.A1.22 - VLT
®
is a registered Danfoss trademark
6-31
6