Class A albedometer SRA30-M2-D1

spectrally flat

Overview
The all-digital heated SR30-M2-D1 offers the highest accuracy and highest data availability: it outperforms pyranometers equipped with traditional ventilation systems. After introduction in 2017, SR30 was rapidly recognised as the ideal instrument for use in PV system performance monitoring, and is increasingly used in meteorological networks as well. SR30 is an ISO 9060 spectrally flat Class A pyranometer. It measures the solar radiation received by a plane surface, in W/m², from a 180° field of view angle. SR30 offers many advantages over competing pyranometers.

Key features
• Class A performance: fully compliant with ISO 9060:2018 spectrally flat Class A classification (ISO 9060:1990 secondary standard) and meets IEC 61724-1 Class A PV monitoring system requirements.
• Recirculating Ventilation and Heating (RVH™): heats the outer dome by ventilating air in a closed circuit between the inner and outer dome, consuming less than 3 W compared to 10 W for traditional ventilation systems while eliminating filter maintenance.
• Calibrated tilt sensor: individually calibrated and temperature-compensated between -30 and +50 °C, providing tilt measurements accurate within ± 1° as required by IEC 61724-1 for single-axis tracker monitoring and fault detection.
• Spectrally flat: WMO compliant and suitable for Global Horizontal Irradiance (GHI), Plane of Array (POA), albedo, and diffuse radiation measurements with negligible spectral errors.
• Operation in 3 power modes: supports normal (< 3 W, heated and ventilated), medium (< 0.65 W), and low-power mode (< 0.1 W, unheated and unventilated), complying with ISO 9060 Class A in all three modes.
• Remote sensor diagnostics: outputs digital diagnostics over Modbus RTU, including instrument body temperature, tilt angle, internal humidity, ventilator speed (RPM), and heater current to reduce unnecessary field inspections.
• Supplied with DP01 dome protector: mitigates the risk of damage during transport, installation, and recalibration cycles to avoid unnecessary repair costs.
• Lowest total cost of ownership: backed by a worldwide calibration organisation to simplify recalibration every 2 years and minimize operating and maintenance costs.
SRA30-M2-D1

Applications
• PV system performance monitoring (commercial and utility-scale, fixed-tilt and single-axis trackers).
• Plane of Array (POA) and Global Horizontal Irradiance (GHI) measurement.
• High-accuracy scientific meteorological observations and weather networks.
• High-accuracy diffuse radiation and albedo measurements.

Specifications
• Measurand: hemispherical solar radiation [W/m²]
• Additional measurand: sensor tilt angle [°]
• ISO 9060:2018 classification: spectrally flat Class A pyranometer
• ISO 9060:1990 classification: secondary standard pyranometer
• WMO performance level: high quality pyranometer
• IEC 61724-1 compliance: meets Class A PV monitoring system requirements for solar irradiance and tracker tilt angle measurements for all locations and climatic conditions
• Calibration uncertainty: < 1.2 % (k = 2)
• Calibration traceability: to WRR (World Radiometric Reference)
• Spectral range: (285 to 3000) x 10⁻⁹ m
• Zero offset a: < 2 W/m²
• Rated operating temperature range: -40 to +80 °C
• Temperature response (-30 to +50 °C): < ± 0.4 %
• Tilt measurement uncertainty (-30 to +50 °C, 0 to 90° tilt): ± 1°
• Power consumption (at 12 VDC): normal mode < 3 W, medium mode < 0.65 W, low mode < 0.1 W
• Rated operating voltage range: 8 to 30 VDC
• Communication protocol: Modbus RTU
• Hardware interface: 2-wire (half duplex) RS-485
• Digital output: irradiance in W/m², instrument body temperature in °C, tilt angle in °, internal humidity in %, ventilator speed in RPM
• Standard cable length: 5 m
• Dome protector: model DP01 included

Optional accessories and mounting options
• Standard cable length: 5 m
• Longer cable options: 10 m and 20 m
• LM01: spring-loaded levelling mount for flat surfaces
• TLM01: tube levelling mount with set of bolts
• PMF01 and PMF02: mounting fixtures for horizontal and Plane of Array (POA) installations
• AMF03: albedometer fixture
• DP01: dome protector set of 5 pieces