Danfoss VLT HVAC Drive Instruction Manual page 90

6. How to program the adjustable frequency
drive
20-01
Value:
Linear
Square root
Pressure to temperature
Function:
This parameter allows a conversion function
6
to be applied to Feedback 1.
Linear
Square root
pressure sensor is used to provide flow feed-
back (
Pressure to temperature
pressor applications to provide temperature
feedback using a pressure sensor. The tem-
perature of the refrigerant is calculated using
the following formula:
Temperature
are refrigerant-specific constants. The refrig-
erant must be selected in parameter 20-20.
Parameters 20-21 through 20-23 allow the
values of A1, A2 and A3 to be entered for a
refrigerant that is not listed in parameter
20-20.
20-03
Function:
Feedback 1 Source
See
20-04
Function:
See Feedback 1 Conversion
tails.
90
mines how the three possible
feedbacks will be used by the
PID controller.
Feedback 1 Conversion
[0] has no effect on the feedback.
[1] is commonly used when a
) ).
flow pressure
∝
24 is used in com-
A
=
- where A1, A2 and A3
2
Feedback 2 Source
, par. 20-00 for details.
Feedback 2 Conversion
par. 20-01 for de-
MG.11.A4.22 - VLT
VLT
20-06 Feedback 3 Source
Function:
Feedback 1 Source
See
20-07 Feedback 3 Conversion
Function:
See Feedback 1 Conversion
[0]
details.
[1]
[2]
20-20 Feedback Function
Value:
Sum
Difference
Average
Minimum
Maximum
Multi-setpoint min
Multi-setpoint max
Function:
This parameter determines how the three
possible feedbacks will be used to control the
output frequency of the adjustable frequency
drive.
NOTE
Any unused feedback must be
set to "No function" in its Feed-
back Source parameter: 20-00,
20-03 or 20-06.
The feedback resulting from the function se-
lected in par. 20-20 will be used by the PID
Controller to control the output frequency of
the adjustable frequency drive. This feedback
can also: be shown on the adjustable frequen-
cy drive's display, be used to control an ad-
justable frequency drive's analog output, and
be transmitted over various serial communi-
cation protocols.
The adjustable frequency drive can be config-
ured to handle multi-zone applications. Two
different multi-zone applications are suppor-
ted:
® is a registered Danfoss trademark
® HVAC Drive Instruction Manual
, par. 20-00 for details.
, par. 20-01 for
[0]
[1]
[2]
[3]
[4]
[5]
[6]