Kipp&Zonen BSRN Scientific Solar Monitoring System - Manual (Page 109)

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B 2.7 Eppley Black and W hite Pyranom eter (Model 8-48)
The Black and W hite Pyranometer has a detector consisting of a differential therm opile with the hot-junction
receivers blackened and the cold-junction receivers whitened. The receiver is of radial wire-wound plated
construction with the black segm ents coated with a flat black coating and the white with Barium Sulfate.
Built-in tem perature com pensation with therm istor circuitry is incorporated to free the instrum ent from
effects of am bient tem perature. A precision ground optical glass hem isphere of Schott glass W G295 uniform ly
transm its energy from 0.285 to 2.8 :m .
Specifications
Sensitivity approx. 10 :V/W m -2
Im pedance approx. 350 Ohm s
Tem perature Dependence ± 1.5 % over am bient tem perature range -20 to +40 C o
Linearity ± 1.0 % from 0 to 1400 W m -2
Response tim e 5 seconds (1/e signal)
Cosine ± 2 % from norm alization 0-70 zenith angle o
± 5 % from norm alization 70-80 zenith angle o
Mechanical Vibration tested up to 20 g’s without dam age
Calibration integrating hem isphere
Size 5.75 inch diam eter, 2.75 inches high
W eight 2 pounds
B 2.8 Schenk Star Pyranom eter
The m easuring principle of the star pyranom eter is the m easurem ent of, the tem perature difference between
white and black painted sectors so that the result is not affected by am bient tem perature. A precisely cut
dom e shields the sensing elem ents from environm ental factors.
A drying cartidge keeps the interior free from hum idity. An optional protective housing enables m easurem ents
in cold weather.
Technical Data
Measuring range 0 to 1500 W m -2
Spectral sensitivity 0.3 to 3 :m
Output About 15 :V/W m or 4 ... 20 m A = 0 ... 1500 W m -2 -2
Im pedence About 35 Ohm
Am bient tem perature -40 C to +60 C o o
Resolution < 1 W m -2
Stability < 1% per year ( tem porary operation )
Cosine response < 3 % of the value, zenith angle 0 - 80 o o
Azim uth response < 3 % of the value
Tem perature effect < 1 % of the value between -20 C to + 40 C o o