The SI-111 (previously known as the IRR-P) is a precision infrared radiometer made by Apogee Instruments that makes continuous measurements in field conditions. The SI-111 is composed of a thermopile, which measures surface temperature, and a thermistor, which measures sensor body temperature. The two temperature probes are housed in a rugged aluminum body that contains a germanium window. Both the thermopile and the thermistor output a millivolt signal. Our dataloggers measure the millivolt signals and apply the Stefan-Boltzman equation, which corrects for the effect of sensor body temperature on the target temperature.
| Campbell Scientific, Inc. | |
|---|---|
| Product Category | Weather Instruments |
| Product Number | SI-111 |
| Product Name | Apogee Infrared Radiometer |
| Device Classification | Sensor Only |
| Weather Component Sensed | Measures solar Radiation; Measures Temperature |
| Output Options | Outputs an analog voltage signal |
| Wavelength Range Measured | 8000 to 14000 nm (80000 to 140000 Å) |
| Solar Detector Instrument Type | Radiometer |
