[10]
Analog Input X42/3
[11]
Analog Input X42/5
[100]
Bus feedback 1
[101]
Bus feedback 2
[102]
Bus feedback 3
20-07 Feedback 3 Conversion
Option:
Function:
See par. 20-01
for details.
[0] *
Linear
[1]
Square root
[2]
Pressure to temperature
[3]
Pressure to flow
[4]
Velocity to flow
20-20 Feedback Function
Option:
Function:
This parameter determines how the three possible feedbacks will be used to control the output
frequency of the adjustable frequency drive.
[0]
Sum
Sum
[0] sets up the PID Controller to use the sum of Feedback 1, Feedback 2 and Feedback 3 as
the feedback.
NOTE!
Any unused feedbacks must be set to
No Function
in par. 20-00
, or par. 20-06
The sum of Setpoint 1 and any other references that are enabled (see par. group 3-1*) will be used
as the PID Controller’s setpoint reference.
[1]
Difference
Difference
[1] sets up the PID controller to use the difference between Feedback 1 and Feedback
2 as the feedback. Feedback 3 will not be used with this selection. Only Setpoint 1 will be used. The
sum of Setpoint 1 and any other references that are enabled (see par. group 3-1*) will be used as
the PID controller’s setpoint reference.
[2]
Average
Average
[2] sets up the PID Controller to use the average of Feedback 1, Feedback 2 and Feedback
3 as the feedback.
NOTE!
Any unused feedbacks must be set to
No Function
in par. 20-00
, or par. 20-06
. The
sum of Setpoint 1 and any other references that are enabled (see par. group
3-1*) will be used as the PID Controller’s setpoint reference.
[3] *
Minimum
Minimum
[3] sets up the PID controller to compare Feedback 1, Feedback 2 and Feedback 3 and
use the lowest value as the feedback.
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
6-33
6
