SR11 Pyranometer
2
number on your SR11 to ensure that the given calibration constant corresponds
to your sensor.
4. Overview
The SR11 pyranometer is designed for continuous outdoor use. Due to its flat
spectral sensitivity from 285 to 3000 nm, it can be used in natural sunlight,
under plant canopies, in greenhouses or buildings, and inverted to measure
reflected solar radiation. Two SR11s can be used in combination to measure
albedo. The SR11 can also be used to measure most types of artificial light
(Xenon lamps, Halogen lamps, etc.).
The SR11 pyranometer consists of a thermopile sensor, housing, two domes,
and cable. The thermopile is coated with a black absorbent coating. The paint
absorbs the radiation and converts it to heat. The resultant temperature
difference is converted to a voltage by the copper-constantan thermopile. The
thermopile is encapsulated in the housing in such a way that it has a field of
view of 180 degrees and the angular characteristics needed to fulfill the cosine
response requirements.
5. Specifications
Features:
•
Compatible with the following CRBasic dataloggers: CR300 series,
CR6, CR800 series, CR1000, CR3000, CR5000, and CR9000(X)
•
Measures reflected solar radiation when inverted
•
Provides measurements in direct sunlight, under plant canopies, under
cloud cover, and in artificial light
•
Includes bubble level and leve
l
ling screws eliminating need for a
separate leve
l
ling base, simplifying installation
•
Acceptable for providing the solar radiation data used in stability
estimations
•
Double glass dome
Overall classification according to ISO
9060 / WMO:
First class pyranometer
Response time for 95% response:
18 s
Zero offset (response to 200 W m
–2
net
thermal radiation):
5 W m
–2
unventilated
Zero offset (response to 5 K/h change
in ambient temperature):
< 4 W m
–2
Non-stability:
< ±1% change per year
Non-linearity:
< ±1% (100 to 1000 W m
–2
)
Directional response for beam
radiation:
±20 W m
–2
Spectral selectivity:
< ±5% (350 to 1500 nm)
Temperature response:
< ±2% (–10 to 40 °C)
Tilt response:
< ±2% (0 to 90 ° at 1000 W m
-2
)