Net radiometer RA01

solar

Overview
RA01 is a market-leading 2-component radiometer, primarily used in scientific-grade energy balance and surface flux networks. It offers 2 separate measurements of global solar and downward longwave radiation with a pyranometer and a pyrgeometer, respectively. Product features include a modular design, low weight, easy leveling, and low solar offsets in the longwave measurement.

Key features
• 2-component radiation measurement: offers two separate measurements of incoming radiation—global solar radiation (with an ISO 9060:2018 spectrally flat Class C pyranometer) and downward longwave radiation (with a pyrgeometer).
• Heated pyrgeometer: unique capability to heat the pyrgeometer (12 VDC, 1.5 W) reduces measurement errors caused by dew deposition.
• Integrated body temperature sensor: includes a Pt100 temperature sensor inside the instrument body, enabling correction for emitted thermal radiation and derivation of sky temperature.
• Modular design: allows the instrument to be taken apart to easily replace or recalibrate individual sensors.
• 2-axis leveling assembly: includes a 2-axis leveling assembly designed to fit a 1-inch NPS tube, with an included shim for mounting on a 3/4-inch NPS tube.
• Sunshine duration estimation: compatible with the WMO-approved pyranometric method to estimate sunshine duration using the solar radiation sensor.
• Net radiation estimation: when combined with estimates of solar albedo and local surface temperature, it can estimate net radiation cost-effectively and independently of local surface properties.

Applications
• Energy balance studies.
• Surface flux measurements.
• Climatological and meteorological networks.
• Sky temperature and sunshine duration monitoring.

Specifications
• Measurand: global solar radiation [W/m²]
• Measurand: downward longwave radiation [W/m²]
• Optional measurand: sky temperature [°C], sunshine duration [h], estimated net radiation [W/m²]
• Required measurand: instrument body temperature [°C]
• Included sensors: 1 x ISO 9060 spectrally flat Class C pyranometer, 1 x pyrgeometer (150° field of view angle)
• Pyranometer classification: ISO 9060:2018 spectrally flat Class C; WMO Class C
• Calibration traceability (solar): to WRR (World Radiometric Reference)
• Calibration traceability (longwave): to WISG (World Infrared Standard Group)
• Spectral range (solar): 285 to 3000 x 10⁻⁹ m
• Spectral range (longwave): 4.5 to 42 x 10⁻⁶ m
• Temperature sensor: Pt100 (instrument body temperature)
• Required readout: 2 x DC voltage, 1 x Pt100
• Heater on pyrgeometer: 12 VDC, 1.5 W
• Rated operating temperature range: -40 to +80 °C
• Leveling: 2-axis leveling assembly included
• Mounting: on a 1-inch NPS tube (recommended OD: 33.4 x 10⁻³ m); includes shim for 3/4-inch tube (tubes not included)
• Standard cable length: 2 x 5 m

Options and accessories
• Standard cable length: 2 x 5 m
• Longer cable options: in multiples of 5 m; cable lengths above 20 m in multiples of 10 m
• Temperature sensor option: 10 kΩ thermistor instead of Pt100 temperature sensor
• CMF01: crossarm mounting fixture for installing RA01 on a mast
• NR01: 4-component net radiometer alternative for full 4-component surface radiation balance