Pyrgeometer IR02

IR02 is a pyrgeometer used for longwave irradiance measurements in meteorological applications. The instrument can be heated, which improves measurement accuracy by mitigating dew and frost deposition on its window. Because of features like this, IR02 is popular and often used in agricultural networks. IR02 measures the longwave or far-infrared radiation (FIR) received by a plane surface, in W/m², from a field of view angle of approximately 150 °. Longwave radiation is the portion of atmospheric radiation not emitted by the sun. While the actual field of view angle is not the ideal 180 °, the reduction makes it possible to offer IR02 at an attractive price level with only a minor loss in accuracy. IR02 has a window with a cut-on at 4.5 x 10⁻⁶ m, making it suitable for both day and night observations. Benefits The IR02 pyrgeometer has a high sensitivity. With sufficient input signal, a typical data logger no longer contributes to the uncertainty of the measurement. It also houses an on-board heater that prevents condensation on the pyrgeometer window, which can otherwise cause significant measurement errors. Operation Using IR02 is easy. It connects directly to commonly used data logging systems. The irradiance in W/m² is calculated by dividing the IR02 output, a small voltage, by the sensitivity while also accounting for the irradiated heat by the sensor itself (Stefan-Boltzmann law). The sensitivity is provided on IR02’s product certificate.