6450 Solar Radiation Pyranometer

The Davis 6450 solar radiation sensor is required (along with an anemometer and a temperature/humidity sensor) if you wish to monitor evapotranspiration.
Diffuser element and housing are carefully designed for accurate cosine response. Silicon photo diode provides good match to solar spectrum. Two-piece housing minimizes radiation heating, allows convection cooling of the sensor, and prevents the trapping of water or dust. Includes built-in level and 2' (0.6 m) cable.

Operating Temperature:  -40° to +150° F (-40° to +65° C)
Storage Temperature:  -50° to +158°F (-45° to +70°C)
Transducer:  Silicon photodiode
Spectral Response (10% points): 400 to 1100 nanometers
Cosine Response:
     Percent of Reading:  ±3% (0° to ±70° incident angle); ±10% (±70° to ±85° incident angle)
     Percent of Full Scale: ±2% (0° to ±90°)
Supplied Cable Length:  3' (0.9 m)
Cable Type:  4-conductor, 26 AWG
Connector:  Modular RJ-11
I/O Specifications:
     Green wire: Output (0 to +3VDC); 1.67 mV per W/m2
     Red & Black wires: Ground
     Yellow wire:  +3 VDC ±10%; 1mA (typical)
Temperature Coefficient: +0.067% per °F (+ 0.12% per °C)
     Reference temperature: 77°F (25°C)
     Correction per degree above reference temp:-0.067% of reading per °F (-0.12% per °C)
     Correction per degree below reference temp:  +0.067% of reading per °F (+0.12% per °C)
Housing Material: UV-resistant PVC plastic
Dimensions (Length x Width x Height):  2.00” x 2.75” x 2.25” (51 mm x 70 mm x 57 mm)
Weight:  0.5 lbs. (226 g)

Sensor Output:
Resolution and Units: 1 W/m2
Range:  0 to 1800 W/m2
Accuracy:  ±5% of full scale (Reference: Eppley PSP at 1000 W/m2) plus 45 W/ m2 per 100' (30 m) of additional cable
Drift: up to ±2% per year
Update Interval:  50 seconds to 1 minute (5 minutes when dark)