Schako VAQS DS0 Series, Руководство пользователя

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Volumetric flow controller VAQS
®
08/23 - 12
Construction subject to change. No return possible!
09.05.2019 Version:
Setting the operating potentiometers / calculation
formulae
Set value for V
max
The required volumetric flow that is to flow at the 10 V DC com-
mand signal at terminal 3 (Y) or with positive control V
max
is set
in % at the V
max
potentiometer of the controller, the ZTH-EU or
PC-Tool. This value refers to the set
V
nenn
nominal volumetric
flow.
Set value for V
min
The required volumetric flow that is to flow at the 0 V DC com-
mand signal (operating mode 0-10 V DC) or at the 2 V DC com-
mand signal (operating mode 2 - 10 V DC) at terminal 3 (Y) or
with positive control V
min
is set in % at the V
min
potentiometer
of the controller, the ZTH-EU or PC-Tool. This value refers to the
set V
nenn
volumetric flow.
Calculation of the U
5
voltage value
Operating mode: 2 - 10 V DC:
V
max
values
V
min
values
Operating mode: 0 - 10 V DC:
V
max
values
V
min
values
Calculation of the V
nenn
volumetric flow
[m³/h]
The calibration curve is usually
12 m/s. Upon customer request,
a smaller value can be selected.
Actual value measurement via feedback signal U
5
using a
voltmeter or PC-Tool
LMV/NMV-D3-MF
Supply voltage: 24 V AC/DC
(Terminals 1+2)
Measurement output 2 - 10 V DC
(Terminals 1+5)
Measurement output 0 - 10 V DC
(Terminals 1+5)
The actual value signal U
5
is a real feedback of the volumetric
flow actual value for monitoring and controlling the air through-
put volume.
U
5
signal 0-10 V DC
Example
U
5
signal 2-10 V DC
Example
Attention: The V
nenn
value changes as a function of the set cal-
ibration curve.
EWV
max
Vmax
Vnenn
---------------- 100%
×
=
EWV
min
Vmin
Vnenn
---------------- 100%
×
=
U5
Vmax
Vnenn
---------------- 8V 2V
+
×
=
U5
Vmin
Vnenn
---------------- 8V 2V
+
×
=
U5
Vmax
Vnenn
---------------- 10V
×
=
U5
Vmin
Vnenn
---------------- 10V
×
=
Vnenn EK F 3600
× ×
=
EW (%) = Set value
EK (m/s) =
Calibration
curve
U
5
(V DC) = U
5
signal
F (m²) = Area
Assume: Measurement output signal U
5
= 6.3 V DC
Calibration value VAQS = 12 m/sec
Measured value: Duct velocity = 7.6 m/s
Air volume:
Duct velocity x area m² x 3600 = m³/h
Assume: Measurement output signal U
5
= 6.3 V DC
Calibration value VAQS = 12 m/sec
Measured value: Duct velocity = 6.3 m/s
Air volume:
Duct velocity x area m² x 3600 = m³/h