VLT
®
8000 AQUA
1 setpoint and 1 feedback
If only 1 setpoint and 1 feedback signal are used,
parameter 418
Setpoint 1
will be added to the remote
reference. The sum of the remote reference and
Setpoint 1
becomes the resulting reference, which will
then be compared with the feedback signal.
1 setpoint and 2 feedbacks
Just like in the above situation, the remote reference
is added to
Setpoint 1
in parameter 418. Depending
on the feedback function selected in parameter
417
Feedback function
, a calculation will be made
of the feedback signal with which the sum of the
references and the setpoint is to be compared. A
description of the individual feedback functions is
given in parameter 417
Feedback function
.
2 Setpoints and 2 feedbacks
Used in 2-zone regulation, where the function selected
in parameter 417
Feedback function
calculates the
setpoint to be added to the remote reference.
416 Feedback conversion
(FEEDBACK CONV.)
Value:
✭
Linear (LINEAR)
[0]
Square root (SQUARE ROOT)
[1]
Function:
In this parameter, a function is selected which
converts a connected feedback signal from the
process to a feedback value that equals the
square root of the connected signal.
This is used, e.g. where regulation of a flow (volume) is
required on the basis of pressure as feedback signal
(flow = constant x
√
pressure). This conversion makes
it possible to set the reference in such a way that there
is a linear connection between the reference and the
flow required. See drawing in next column.
Feedback conversion should not be used if
2-zone regulation in parameter 417
Feedback
function has been selected.
Description of choice:
If
Linear
[0] is selected, the feedback signal and
the feedback value will be proportional.
If
Square root
[1] is selected, the AFD translates the
feedback signal to a square root value.
✭
= factory setting. () = display text [] = value for use in communication via serial communication port
MG.80.A7.22 - VLT is a registered Danfoss trademark
136
Rosewood STP ST42 General (Operation and Maintenance Manual - Part 4:
Section 6.3 Manufacturers Manuals 6.3.33 Danfoss VLT Aquadrive 8000) Vendor Manual
QP Id: VM207
Active: 03/09/2013
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