CIR 4
(CLoud Infrared Radiometer)
The Solution for Day and Night Nebulosity Measurement
Up to now measurements of the cloud
cover are still
performed by human observers with a low frequency around once every
three hours
or by ceilometers (ASOS algorithm). In parallel new challenges in
meteorology,
climatology and environmental protection require accurate and frequent
measurements of this parameter day and night.
Principle:
The infrared technology of CIR 4
answers this
challenge. Indeed, it allows the measurement of nebulosity day and
night and
associated parameters with a frequency up to once per minute. The
transmission
is done at the same rate as any type of remote systems with serial
inputs
(RS485) and optionally with voltage inputs.
Each of the four detectors points to
one of the
ordinal wind directions (N, E, S, W).
CIR 4 provides in the transmitted data
string:
- Global
Nebulosity in percent or octa (user selectable)
- Nebulosity per
cloud height class in percent or octa (user selectable)
- Ceiling per
cloud height class in meters or feet (set by the user)
- Main direction
where clouds are located (ordinal)
Technical
Features:
- Nebulosity:
Range: 0 to 100%
Accuracy: +/- 6%
- Ceiling:
Range: 0 - 8000 m
Accuracy: +/- 200 m (with adiabatic profile)
- Power supply: 12-30 VDC (450mA)
- Installation: 1-1/2” pipe
(34mm)
- Dimensions: 150x150x300mm
(mounting post included)
- Communication: The transmitted data
string is
terminated at its end by control characters <CR/LF>. A
polled mode is
also available with an address to manage multiple sensors
- Parameters: a software
under Windows
2000 or XP
(CQCOM) is supplied with the instrument
Options :
- Communication
box : RS232
- Power supply
- Cable and reel
- Analogic converter
- CQ tracker: software which
allows the integration
and storage of the data sent by CIR 4
- Portable tripod with its
guy wire assembly
- Carrying case
- Checking by
Atmos of the sensor with a conformity certificate
- Possibility
to rent the sensor
Benefits :
Thanks
to its 4 detectors, CIR 4 allows a better description of the sky dome
than a ceilometer using the ASOS algorithm. A ceilometer provides an
accurate value of the ceiling within one point whereas CIR 4 provides
statistical ceiling height over an important number of points.
Concerning
the nebulosity, an automatic process provides a better reliability and
repeatability of the data.
Its
low consumption allows the deployment of the instrument on all kinds of
locations even remote ones.
Finally,
its passive infrared technology dos not affect the surrounding
environment.