Specifications – Casella CEL Multimet User Manual
Page 15
5.
SPECIFICATIONS
5.1
Anemometer Wind Speed Sensor
Transducer type:
Optical interrupter
Maximum wind speed:
75 m/s
Starting velocity:
Typically 0.3 m/s
Distance constant:
3.5 m/s
Time constant:
Typically <0.5 s
Output calibration:
12.75 Hz/m/s
Resolution:
7.84 cm
Output signal:
0 - 5 V pulses
Pulses/revolution:
20
Non-linearity:
<±0.6%
Accuracy:
±0.3 m/s below 3 m/s
±1% over 3 m/s
Supply voltage:
6 to 28 V DC
Power consumption:
3 mA
Stabilisation time:
<1 s from power up
Operating temperature:
-20 to +70
o
C
Heater option:
24 V DC / AC, 82 Ω, 7 W
Connecting cable:
4.5 m without conduit
3.25 m with conduit
Conduit:
2.55 m
5.2
Weathervane Wind Direction Sensor
Transducer type:
GMR solid state system with
microcontroller
Maximum wind speed:
75 m/s
Resolution:
1
o
Accuracy:
<±2
o
Aligning threshold:
<0.8 m/s for a 10
o
offset
Damping ratio:
0.25
Distance constant:
Typically 3.0 m
Undamped natural wavelength:
2.2 m
Repeatability:
0.5% FSD
Electrical angle:
0 to 359
o
no deadband at North
Nominal output signal:
0 to 1.8 V DC for 0 to 359
o
representing a 1 s rolling average updated
5 times per second
NMEA serial output:
When anemometer is connected, 0 to 5 V
level data containing both direction and
speed information updated 4 times per
second
Supply voltage:
6 to 28 V DC
Power consumption:
3 mA
Stabilisation time:
<1 s from power up
Operating temperature:
-20 to +70
o
C
Specifications
Page 15 of 16
MULTIMET Wind Speed and Direction System
& OnlinePro Software - Users Handbook