SP-230-SS: All-Season Heated Pyranometer

$248.00

The SP-230 (All-season) is a heated pyranometer with a 0.2 W heater to keep water (liquid and frozen) off the sensor and minimize errors caused by dew, frost, rain, or snow blocking the optical path. Sensor includes IP67 marine-grade stainless-steel cable connector 30 cm from head to simplify sensor removal and replacement for maintenance and recalibration.

Figure 1: Solar radiation after a January frost in Logan, Utah with overcast conditions until 11 a.m. The two replicate Apogee SP-230 pyranometers were nearly identical to a heated and ventilated reference pyranometer. In spite of the bright sunlight after 11 a.m., the frost on two unheated glass dome thermopile and four replicate unheated castle design pyranometers did not melt until after 4 p.m. (1600 hours).

Figure 1: Solar radiation after a January frost in Logan, Utah with overcast conditions until 11 a.m. The two replicate Apogee SP-230 pyranometers were nearly identical to a heated and ventilated reference pyranometer. In spite of the bright sunlight after 11 a.m., the frost on two unheated glass dome thermopile and four replicate unheated castle design pyranometers did not melt until after 4 p.m. (1600 hours).

Figure 2. The effect of frost and snow accumulation for three groups of pyranometers in Logan UT, expressed as a percentage of true reading. Castle design and unheated thermopile sensors averaged a 20% error for the month with a maximum error of 80%. Data for Figure 1 is from day 12.

Figure 2. The effect of frost and snow accumulation for three groups of pyranometers in Logan UT, expressed as a percentage of true reading. Castle design and unheated thermopile sensors averaged a 20% error for the month with a maximum error of 80%. Data for Figure 1 is from day 12.

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The SP-230 (All-season) is a heated pyranometer with a 0.2 W heater to keep water (liquid and frozen) off the sensor and minimize errors caused by dew, frost, rain, or snow blocking the optical path. Sensor includes IP67 marine-grade stainless-steel cable connector 30 cm from head to simplify sensor removal and replacement for maintenance and recalibration.

Figure 1: Solar radiation after a January frost in Logan, Utah with overcast conditions until 11 a.m. The two replicate Apogee SP-230 pyranometers were nearly identical to a heated and ventilated reference pyranometer. In spite of the bright sunlight after 11 a.m., the frost on two unheated glass dome thermopile and four replicate unheated castle design pyranometers did not melt until after 4 p.m. (1600 hours).

Figure 1: Solar radiation after a January frost in Logan, Utah with overcast conditions until 11 a.m. The two replicate Apogee SP-230 pyranometers were nearly identical to a heated and ventilated reference pyranometer. In spite of the bright sunlight after 11 a.m., the frost on two unheated glass dome thermopile and four replicate unheated castle design pyranometers did not melt until after 4 p.m. (1600 hours).

Figure 2. The effect of frost and snow accumulation for three groups of pyranometers in Logan UT, expressed as a percentage of true reading. Castle design and unheated thermopile sensors averaged a 20% error for the month with a maximum error of 80%. Data for Figure 1 is from day 12.

Figure 2. The effect of frost and snow accumulation for three groups of pyranometers in Logan UT, expressed as a percentage of true reading. Castle design and unheated thermopile sensors averaged a 20% error for the month with a maximum error of 80%. Data for Figure 1 is from day 12.

Google's Project Loon
Apogee's SP-230 heated pyranometer was selected to monitor PV panels on Project Loon.
Monitoring PV Panels on Jin Jeop Library
SP-110's are integrated as part of a PV monitoring sytem for a PV power generation facility on the roof of the Jin Jeop library in Korea.
Solar Power Plants on Lakes and Dams
Studying solar radiation at different angles to determine locations for solar power plants.
Irrigation Study
Pyranometer mounted on model train to collect measurements in orchard for irrigation study.
Current Stock:
Power Supply 12 V DC for heater with a current draw of 15.4 mA Heater 780 Ω, 15.4 mA current draw and 185 mW power requirement at 12 V DC Sensitivity 0.2 mV per W mˉ² Calibration Factor (reciprocal of output) 5 W mˉ² per mV Calibration Uncertainty ± 5 % Calibrated Output Range 0 to 400 mV Measurement Repeatability Less than 1 % Non-stability (Long-term Drift) Less than 2 % per year Non-linearity Less than 1 % (up to 2000 W mˉ²) Response Time Less than 1 ms Field of View 180 ˚ Spectral Range 360 to 1120 nm (wavelengths where response is 10 % of maximum) Directional (Cosine) Response ± 5 % at 75˚ zenith angle Temperature Response 0.04 ± 0.04 % per C Operating Environment -40 to 70 C; 0 to 100 % relative humidity; can be submerged in water up to depths of 30 m Dimensions 24 mm diameter, 28 mm height Mass 90 g (with 5 m of lead wire) Warranty 4 years against defects in materials and workmanship