CNR4

The CNR4 net radiometer consists of a pyranometer pair, one facing upward, the other facing downward, and a pyrgeometer pair in a similar configuration. The pyranometer pair measures the short-wave radiation, and the pyrgeometer pair measures long-wave radiation.

The upper long-wave detector of CNR4 has a meniscus dome. This ensures that water droplets roll off easily and improves the field of view to nearly 180°, compared with a 150° for a flat window. All four sensors are integrated directly into the instrument body, instead of separate modules mounted onto the housing. But each is calibrated individually for optimal accuracy.

Two temperature sensors, a Pt-100 and Thermistor, are integrated for compatibility with every data logger. The temperature sensor is used to provide information to correct the infrared readings for the temperature of the instrument housing. Care has been taken to place the long-wave sensors close to each other and close to the temperature sensors. This assures that the temperatures of the measurement surfaces are the same and accurately known, which improves the quality of the long-wave measurements.

The design is very light in weight and has an integrated sun shield that reduces thermal effects on both long-wave and short-wave measurements. The cables are yellow with waterproof connectors as used with all our new radiometers. The mounting rod can be unscrewed for transport.

An optional ventilation unit with heater is designed as an extension of the sunshield and can be fitted new to the CNR4 or retro-fitted later. This unit is compact and provides efficient air-flow over the domes and windows to minimise the formation of dew and reduce the frequency of cleaning. The integrated heater can be used to melt frost.

The CNR4 specifications comply with the WMO classification of Good Quality.

(*) This product will need to be registered by the end-user within 6 months of purchase to activate the 5 year warranty.