Volumetric flow controller VAQS
®
08/23 - 16
Construction subject to change.
No return possible!
09.05.2019
Version:
Maintenance and service
Assembly and maintenance instructions
Cleaning of the dynamic differential pressure sensor
The dynamic differential pressure sensor integrated into the
LMV/NMV-D3-MF
requires little maintenance. However, if, de-
pending on the degree of pollution of the air, unexpected volu-
metric flow deviations occur, then the following procedure is
recommended.
Legend
1. When the device is delivered, check whether the controllers
are complete and have been delivered without damage.
Complaints have to be communicated immediately and di-
rectly to the transporter and SCHAKO.
2. The volumetric flow controller must not be carried on the
regulation components, measuring cross or the damper
leaf, but only on the housing.
3. The controllers must be carefully stored on-site. They must
be protected from dust, dirt and from direct weather effects.
4. The controllers must be assembled in a way to allow in-
spection.
5. Assembly must be carried out by expert personnel, observ-
ing recognised technical rules and regulations.
6. For polluted air, the volumetric flow controllers must be
used with an integrated controller with a static membrane
pressure sensor. In this case, it is absolutely necessary
to observe the mounting position. The volumetric flow
controllers are not suitable for air containing sticky and
greasy particles.
1. Pull off the pressure hoses from the sensor connection pipe
of the LMV/NMV-D3-MF.
Attention!
Make a note of the (+) and (-) assignments.
2. Using a suitable hand pump, blow air into the (-) connection
spigot of the sensor (this will blow any dirt deposited inside
the sensor out of the (+) connection spigot).
3. Remove any dirt that may have formed from the connecting
pieces and hose ends.
4. Reconnect pressure hoses, (+) and (-) as before.
5. Carry out a functional check of the controller.
V
(m³/h) [l/s] = Air volume
V
min
(m³/h)
= Minimum air volume
V
max
(m³/h)
= Maximum air volume
EW
Vmax
(m³/h)
= Set value of maximum air volume
V
Nenn
(m³/h)
= Nominal air volume
v
K
(m/s)
= Duct velocity
D
e
[dB/Oct]
= Insertion loss
∆
p
t
(Pa)
= Pressure loss
∆
p
t min
(Pa)
= Minimum static pressure difference
L
W
[dB/Oct]
= Sound power level/octave
L
WA
[dB(A)]
= A-weighted sound power level
f
m
(Hz)
= Octave band centre frequency
U5
(V) DC
= Measurement output (electric voltage)
NW
(-)
= Nominal width
