AIR FLOW RATE
CALCULATOR
Technical Notice
FI 72.0190.1021E
Page 2 of 12
SUMMARY:
Page
- DESCRIPTION
2
- OPERATING PRINCIPLE
2
- PRESENTATION OF THE
FRONT FACE
3
- OPERATION OF THE
MENUS
3
- MENU MEASUREMENTS
4
- MENU PARAMETERS
5
- OPERATION OF THE
ALARMS
8
- CHARACTERISTICS
9
- PRECAUTIONS
9
- CONNECTIONS
10
- SPACE REQUIREMENTS
AND FIXINGS
11
- NOTICE
12
- CALIBRATION
12
- MAINTENANCE
12
- WARRANTY
12
- CONFORMITY
12
DESCRIPTION:
The DBX2000 is a device for the calculation of the air flow rate in a
duct using a differential pressure measurement (Pitot tube,
diaphragm, Venturi meter) corresponding to the dynamic pressure.
It has a navigator and a back-lit LCD display for dialogue with the
user.
It is equipped as standard with:
-
1 differential pressure sensor: scale 0-100mmCE
-
2 alarm relays (mini flow rate and maxi flow rate)
-
temperature correction (manual input)
-
absolute pressure correction (manual input)
It may be equipped with:
-
1 analogue input 4-20mA for measurement of the
temperature
-
1 additional sensor for the measurement of the absolute
pressure
-
1 or 2 analogue outputs 4-20mA
-
2 additional alarm relays (temperature and absolute pressure)
OPERATING PRINCIPLE:
The DBX2000 determines the air speed by applying the equation:
with:
-
v
: speed in m/s
-
K
: coefficient of the measurement
-
DP
: dynamic pressure measured in mmCE
-
g
: 9.81 m/s
2
-
: density of the air kg/m3
where:
with
-
PAbs
: absolute pressure in mbar
-
T
: temperature in degrees C
-
0 =1,293
According to the section, the DBX2000 deduces the values of the air
flow m
3
/s, m
3
/h, Nm
3
/s or Nm
3
/h.
g
DP
K
v
2
.
.
=
0
)
273
(
273
25
,
1013
+
=
T
PAbs
