Envco – Environmental Equipment

The SR11 pyranometer is suitable for measuring global short-wave solar irradiance incidenting a plane surface, offering a full 180° field of view (FOV). Capable of measuring up to two suns, 2000 W/m2, the SR11 is also well suited for higher intensity indoors artificial lamp measurement applications. Employing entirely passive thermopile-based sensing technology, the SR11 generates a low level DC millivolt output signal proportional to the solar short-wave flux received at the detector surface.

The instrument design serves to reduce the possibility of wind related signal noise and thermal offset related error effects by employing a set (two) of precision ground and polished glass domes, resulting in improved measurement accuracy. Determining short-wave solar irradiance requires connection to either a data logger or digital voltmeter with a measurement resolution of ten micro-volts or better; simply divide the SR11 millivolt output signal by the factory supplied calibration factor to arrive at irradiance in W/m2 units.

Applications
• Agrometeorology
• Climatology / Meteorology
• Industrial Light Measurement & Process Control
• Material Testing Research
• Solar Collector & PV Panel Efficiency Validation

Typical SR11 measurement applications include scientific meteorological observations, building physics, climate and solar collector/PV panel efficiency testing.

For conventional horizontal plane mounting applications requiring accurate leveling, the SR11 is equipped standard with adjustable leveling feet and a bulls-eye bubble level.

SR11 SPECIFICATIONS
ISO classification: First Class
Spectral range: 305 to 2800 nm
Sensitivity (nominal): 15 μV/W/m2
Response time (95%): 13 sec.
Directional error (1000 W/m2 beam): ± 20 W/m2
Range : 0 to 2000 W/m2
Non-linearity (to 1000 W/m2): ± 1%
Temperature range: -40 to +80° C
Temperature dependence: < ± 0.1 %/°C
Calibration traceability: WRR
Non stability (drift): < ± 1% per year
Cable length: 5 meter standard (longer lengths optional)

The SR11 signal cable can be easily installed and replaced by the user, thus minimizing down-time and expense otherwise associated with instrument re-cabling by the manufacturer.

APPLICABLE STANDARDS
ISO 9060 and 9847, WMO (World Meteorological Organization) and ASTM E824-94. The SR11 can also be used for stability estimations according to EPA (EPA-454/R- 99-005); also see LP02 ISO Second Class Pyranometer model for lower cost instrument alternative.

Ordering Information
SR11 First Class pyranometer
Screen SR11 Radiation screen for SR11