Kipp&Zonen BSRN Scientific Solar Monitoring System - Manual (Page 113)

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Receiver Cavity with inverted cone shaped bottom , coated with specular black paint cavity
(absorptance : >.9998).
Detector Electrically calibrated differential heat flux transducer with resistance therm om eters
as sensors
Accuracy Measurem ent uncertainty (referred to SI-Units) < ± 0.25%
Precision ± 0.01%
Mechanical Dim ensions
Diam eter 75 m m
Length 200 m m
W eight, approx. 2.2 kg
Field of view
(full angle)
5/
Slope angle 1/
Receiver aperture
diam eter (nom inal)
5 m m
Control Electronics
Plug-in circuits (electronic prints) inserted in a cabinet with power supply and control
panel
Cabinet width 290 m m
height 70 m m
depth 330 m m
Power Supply 110 V/220 V
50 Hz/60 Hz
10 W
B 3.3 Eppley Norm al Incidence Pyrheliom eter
The Eppley Norm al Incidence Pyrheliom eter (NIP), as the nam e im plies, was designed for the m easurem ent
of solar radiation at norm al incidence.
The NIP incorporates a wire-wound therm opile at the base of a tube, the aperture of which bears a ratio
to its length of 1 to 10, subtending an angle of 5°43'30". The inside of the brass tube is blackened and
suitably diaphragm ed. The tube is filled with dry air at atm ospheric pressure and sealed at the viewing
end by an insert carrying a 1 m m thick, Infrasil II window. Two flanges, one at each end of the tube, are
provided with a sighting arrangem ent for aim ing the pyrheliom eter directly at the sun. A m anually rotatable
wheel which can accom m odate three filters, while leaving one aperture free, is provided.
The pyrheliom eter is m ounted on a power-driven equatorial m ount for continuous readings.
A calibration certificate traceable to the W orld Radiation Reference and a tem perature com pensation
curve are included.
Specifications
Sensitivity approx. 8 µV W m -1 2
Im pedance approx 200 S
Tem perature Dependence ±1% over the am bient tem perature range -20° +40° C
(tem perature com pensation of sensitivity can be supplied over
other ranges at additional charge)