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Standard Precision Pyranometer

Model SPP

A pyranometer is used to measure the energy from the sun. When leveled in the horizontal plane, this is called the Global Shortwave Irradiance (GLOBAL) and when positioned in a plane of a PV Array, it is called the Total Irradiance in the plane of array (TPA). Inverted, a pyranometer is used to measure the Reflected or Albedo Irradiance (ALBEDO). A pyranometer can also be shaded from the direct beam of the sun to measure the Diffuse Shortwave Irradiance (DIFFUSE).

Uses:

Based on the design of the distinguished PSP Pyranometer, the new SPP has faster response time, a reduced nighttime thermal offset, an improved cosine response and a better temperature dependence. This makes the SPP the ideal instrument for high quality network measurements and as a transfer standard for calibration of other pyranometers. A thermistor is included for measuring instrument temperature.

*Uncertainty:
Recently, there has been much discussion on “uncertainty” and how it pertains to solar measurements. The RSS of the 9060 Secondary Standard specifications results in an uncertainty of approximately 3.5%. The typical uncertainty of Eppley’s factory calibrations are less than 1%. The stated uncertainty of the WRR is 0.4%. Evidence from comparisons of SPP measurements to component sum derived values (using an AHF and 8-48) show the SPP is capable of hourly averages better than 2% and daily averages better than 1%.

CLICK HERE to download Specifications [PDF]

Application Working Standard or Network Measurements
Classification Secondary Standard / High Quality
Traceability World Radiation Reference (WRR)
Spectral Range 295-2800 nm
Output 0-10 mV analog
Sensitivity approx. 8 μV / Wm-2
Impedance approx. 700 Ω
95% Response Time 5 s
Zero Offset a) 5 Wm-2
Zero Offset b) 2 Wm-2
Non-Stability 0.5%
Non-Linearity 0.5%
Directional Response 10 Wm-2
Spectral Selectivity 2%
Operating Temperature -50°C to +80°C
Temperature Response 0.5% from -30°C to +50°C
Tilt Response 0.5%
Calibration Uncertainty* < 1%
Measurement Uncertainty*
Single Point < 10 Wm-2
Hourly Average approx. 2%
Daily Average approx. 1%

CLICK HERE for ISO 9060 Specifications