Casella CEL Indoor air quality monitor - Manual (Page 30)

12.2 Air Velocity Probe
This is a solid state omni-directional air flow
sensor with integrated electronics to provide
power and signal to the sensing element, resulting
in a voltage output relative to air velocity. The
sensor operation is based on the “Hot Wire”
principle.
The sensor is provided with a protective cap that
should be removed by unscrewing it from the
main body of the sensor before use. The
protective cap should be replaced when the sensor
is not in use to prevent damage to the sensor
element.
Care should be taken not to expose the sensor to
corrosive and other harmful gases. Corrosion
proof versions are available.
Sensor Specifications
Specification
Flow Range 0.06 to 2.50 m/S
Maximum Operating Humidity 95% RH (non-condensing)
Air Pressure Range 700 - 1200 hPa
Lower Detection Limit 0.06 m/S
Response Time (T
90
) 1 S
Accuracy for a Given Flow Range 0.06 to 0.3 m/S ± 0.05 m/S
0.3 to 1.5 m/S ± 5% of value
1.5 to 2.5 m/S ±1.5% of value
Air Flow Angle Independent in longitude axis
compensated within a flow angle
from -30
o
C to +60
o
C
Operating Temperature Range -20
o
C to +60
o
C
Calibration Under normal operating
conditions, a calibration check
should be carried out after 6000
hours of operation or 12
months, whichever occurs the
sooner
Connection Type 7 pin socket
Operating Voltage +15 V DC ±0.1 V at 100 mA
The sensor can be factory configured to provide air temperature measurement
in addition to air velocity.
Measuring Sensitivity 60 mV/K
Accuracy ±0.5 K (under flow conditions)
Output Values (Linear) 1.268 V at 0
o
C - 2.409 V at 60
o
C
Page 30 of 42
MICROTHERM indoor air quality &
WinIaq Application Software - User Manual