The NR-LITE is used for measuring solar and far infrared radiation balance. This balance is known as the net (total) radiation. Its upwards facing sensor measures the solar energy and far infra-red energy that is received from the entire hemisphere (180° field of view). Its downwards facing sensor measures the energy received from the surface of the soil. The two readings are automatically subtracted and the result converted to a single output signal. This output represents the net radiation, (which can be interpreted as meaning the radiative energy that is seen at the surface) and is expressed in Watts per square meter (W m-2).
The NR-LITE is designed for continuous outside use. The sensor surfaces are coated with Teflon. This ensures good sensor stability, very long life and easy maintenance compared to the more usual radiometers fitted with plastic domes. However, it does have some disadvantages, particularly a higher sensitivity to wind speed with a subsequent lessening of accuracy. It is, though, possible to correct for the wind speed sensitivity if the sensor is installed in a system where wind speed is also being measured.
Although net radiometers are usually used in meteorology to measure radiation balance, the NR-LITE can also be used to measure indoor climate radiative stress.
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