Danfoss VLT Series Programming Manual page 133

Parameter Description
20-20 Feedback Function
Option:
3 3
[4] Maximum
[5] Multi
Setpoint
Min
[6] Multi
Setpoint
Max
132
VLT
Function:
NOTE
Any unused feedbacks must be set to No
Function in 20-00 Feedback 1 Source,
20-03 Feedback 2 Source, or 20-06 Feedback
3 Source. Only setpoint 1 will be used. The
sum of Setpoint 1 and any other
references that are enabled (see meter
group 3-1*) will be used as the PID
Controller's setpoint reference.
Maximum [4] sets up the PID Controller to com
Feedback 1, Feedback 2 and Feedback 3 and
use the highest value as the feedback.
NOTE
Any unused feedbacks must be set to No
Function in 20-00 Feedback 1 Source,
20-03 Feedback 2 Source, or 20-06 Feedback
3 Source.
Only Setpoint 1 will be used. The sum of
Setpoint 1 and any other references that are
enabled (see meter group 3-1*) will be used as
the PID Controller's setpoint reference.
Multi-setpoint minimum [5] sets up the PID
Controller to calculate the difference between
Feedback 1 and Setpoint 1, Feedback 2 and
Setpoint 2, and Feedback 3 and Setpoint 3. It
will use the feedback/setpoint pair in which the
feedback is the farthest below its corresponding
setpoint reference. If all feedback signals are
above their corresponding setpoints, the PID
Controller will use the feedback/setpoint pair in
which the difference between the feedback and
setpoint is the least.
NOTE
If only two feedback signals are used, the
feedback that is not to be used must be
set to No Function in 20-00 Feedback 1
Source, 20-03 Feedback 2 Source or
20-06 Feedback 3 Source. Note that each
setpoint reference will be the sum of its
respective meter value (20-21 Setpoint 1,
20-22 Setpoint 2 and 20-23 Setpoint 3) and
any other references that are enabled (see
meter group 3-1*).
Multi-setpoint maximum [6] sets up the PID
Controller to calculate the difference between
Feedback 1 and Setpoint 1, Feedback 2 and
Setpoint 2, and Feedback 3 and Setpoint 3. It
will use the feedback/setpoint pair in which the
feedback is farthest above its corresponding
MG.11.CC.02 - VLT
®
HVAC Drive Programming Guide
20-20 Feedback Function
Option:
NOTE
Any unused feedback must be set to "No function" in its
Feedback Source meter: 20-00 Feedback 1 Source,
20-03 Feedback 2 Source or 20-06 Feedback 3 Source.
The feedback resulting from the function selected in
20-20 Feedback Function will be used by the PID Controller
to control the output frequency of the frequency
converter. This feedback can also be shown on the
frequency converter's display, be used to control a
frequency converter's analog output, and be transmitted
over various serial communication protocols.
The frequency converter can be configured to handle multi
zone applications. Two different multi zone applications
are supported:
•
Multi zone, single setpoint
•
Multi zone, multi setpoint
®
is a registered Danfoss trademark
Function:
setpoint reference. If all feedback signals are
below their corresponding setpoints, the PID
Controller will use the feedback/setpoint pair in
which the difference between the feedback and
the setpoint reference is the least.
NOTE
If only two feedback signals are used, the
feedback that is not to be used must be
set to No Function in 20-00 Feedback 1
Source, 20-03 Feedback 2 Source or
20-06 Feedback 3 Source. Note that each
setpoint reference will be the sum of its
respective meter value (20-21 Setpoint 1,
20-22 Setpoint 2 and 20-23 Setpoint 3) and
any other references that are enabled (see
meter group 3-1*).